Partial protective effect of intranasal immunization with recombinant Toxoplasma gondii rhoptry protein 17 against toxoplasmosis in mice.

Directory of Open Access Journals (Sweden)

Hai-Long Wang

Full Text Available Toxoplasma gondii (T. gondii is an obligate intracellular protozoan parasite that infects a variety of mammals, including humans. An effective vaccine for this parasite is therefore needed. In this study, RH strain T. gondii rhoptry protein 17 was expressed in bacteria as a fusion with glutathione S-transferase (GST and the recombinant proteins (rTgROP17 were purified via GST-affinity chromatography. BALB/c mice were nasally immunised with rTgROP17, and induction of immune responses and protection against chronic and lethal T. gondii infections were investigated. The results revealed that mice immunised with rTgROP17 produced high levels of specific anti-rTgROP17 IgGs and a mixed IgG1/IgG2a response of IgG2a predominance. The systemic immune response was associated with increased production of Th1 (IFN-γand IL-2 and Th2 (IL-4 cytokines, and enhanced lymphoproliferation (stimulation index, SI in the mice immunised with rTgROP17. Strong mucosal immune responses with increased secretion of TgROP17-specific secretory IgA (SIgA in nasal, vaginal and intestinal washes were also observed in these mice. The vaccinated mice displayed apparent protection against chronic RH strain infection as evidenced by their lower liver and brain parasite burdens (59.17% and 49.08%, respectively than those of the controls. The vaccinated mice also exhibited significant protection against lethal infection of the virulent RH strain (survival increased by 50% compared to the controls. Our data demonstrate that rTgROP17 can trigger strong systemic and mucosal immune responses against T. gondii and that ROP17 is a promising candidate vaccine for toxoplasmosis.

Toxoplasma gondii chromodomain protein 1 binds to heterochromatin and colocalises with centromeres and telomeres at the nuclear periphery.

Directory of Open Access Journals (Sweden)

Mathieu Gissot

Full Text Available BACKGROUND: Apicomplexan parasites are responsible for some of the most deadly parasitic diseases afflicting humans, including malaria and toxoplasmosis. These obligate intracellular parasites exhibit a complex life cycle and a coordinated cell cycle-dependant expression program. Their cell division is a coordinated multistep process. How this complex mechanism is organised remains poorly understood. METHODS AND FINDINGS: In this study, we provide evidence for a link between heterochromatin, cell division and the compartmentalisation of the nucleus in Toxoplasma gondii. We characterised a T. gondii chromodomain containing protein (named TgChromo1 that specifically binds to heterochromatin. Using ChIP-on-chip on a genome-wide scale, we report TgChromo1 enrichment at the peri-centromeric chromatin. In addition, we demonstrate that TgChromo1 is cell-cycle regulated and co-localised with markers of the centrocone. Through the loci-specific FISH technique for T. gondii, we confirmed that TgChromo1 occupies the same nuclear localisation as the peri-centromeric sequences. CONCLUSION: We propose that TgChromo1 may play a role in the sequestration of chromosomes at the nuclear periphery and in the process of T. gondii cell division.

Structure of Toxoplasma gondii fructose-1,6-bisphosphate aldolase

International Nuclear Information System (INIS)

Boucher, Lauren E.; Bosch, Jürgen

2014-01-01

The structure of T. gondii fructose-1,6-bisphosphate aldolase, a glycolytic enzyme and structural component of the invasion machinery, was determined to a resolution of 2.0 Å. The apicomplexan parasite Toxoplasma gondii must invade host cells to continue its lifecycle. It invades different cell types using an actomyosin motor that is connected to extracellular adhesins via the bridging protein fructose-1,6-@@bisphosphate aldolase. During invasion, aldolase serves in the role of a structural bridging protein, as opposed to its normal enzymatic role in the glycolysis pathway. Crystal structures of the homologous Plasmodium falciparum fructose-1,6-bisphosphate aldolase have been described previously. Here, T. gondii fructose-1,6-bisphosphate aldolase has been crystallized in space group P22 1 2 1 , with the biologically relevant tetramer in the asymmetric unit, and the structure has been determined via molecular replacement to a resolution of 2.0 Å. An analysis of the quality of the model and of the differences between the four chains in the asymmetric unit and a comparison between the T. gondii and P. falciparum aldolase structures is presented

A protein extract and a cysteine protease inhibitor enriched fraction from Jatropha curcas seed cake have in vitro anti-Toxoplasma gondii activity.

Science.gov (United States)

Soares, A M S; Carvalho, L P; Melo, E J T; Costa, H P S; Vasconcelos, I M; Oliveira, J T A

2015-06-01

Toxoplasma gondii is a parasite of great medical and veterinary importance that has worldwide distribution and causes toxoplasmosis. There are few treatments available for toxoplasmosis and the search for plant extracts and compounds with anti-Toxoplasma activity is of utmost importance for the discovery of new active drugs. The objective of this study was to investigate the action of a protein extract and a protease inhibitor enriched fraction from J. curcas seed cake on developing tachyzoites of T. gondii-infected Vero cells. The protein extract (JcCE) was obtained after solubilization of the J. curcas seed cake with 100 mM sodium borate buffer, pH 10, centrifugation and dialysis of the resulting supernatant with the extracting buffer. JcCE was used for the in vitro assays of anti-Toxoplasma activity at 0.01, 0.1, 0.5, 1.5, 3.0 and 5.0 mg/ml concentration for 24 h. The results showed that JcCE reduced the percentage of infection and the number of intracellular parasites, but had no effect on the morphology of Vero cells up to 3.0 mg/mL. The cysteine protease inhibitor enriched fraction, which was obtained after chromatography of JcCE on Sephadex G-75 and presented a unique protein band following SDS-PAGE, reduced both the number of T. gondii infected cells and intracellular parasites. These results suggest that both JcCE and the cysteine protease inhibitor enriched fraction interfere with the intracellular growth of T. gondii. Copyright © 2015 Elsevier Inc. All rights reserved.

CCp5A protein from Toxoplasma gondii as a serological marker of oocyst-driven infections in humans and domestic animals.

Directory of Open Access Journals (Sweden)

Silas Silva Santana

2015-11-01

Full Text Available Considering that the current immunoassays are not able to distinguish the infective forms that cause Toxoplasma gondii infection, the present study was carried out to evaluate the reactivity of two recombinant proteins (CCp5A and OWP1 from oocyst/sporozoite, in order to differentiate infections occurring by ingestion of oocysts or tissue cysts. The reactivity of the recombinant proteins was assessed against panels of serum samples from animals (chickens, pigs and mice that were naturally or experimentally infected by different infective stages of the parasite. Also, we tested sera from humans who have been infected by oocysts during a well-characterized toxoplasmosis outbreak, as well as sera from pregnant women tested IgM+/IgG+ for T. gondii, which source of infection was unknown. Only the sporozoite-specific CCp5A protein was able to differentiate the parasite stage that infected chickens, pigs and mice, with specific reactivity for oocyst-infected animals. Furthermore, the CCp5A showed preferential reactivity for recent infection by oocyst/sporozoite in pigs and mice. In humans, CCp5A showed higher reactivity with serum samples from the outbreak, compared with serum from pregnant women. Altogether, these findings demonstrate the usefulness of the CCp5A protein as a new tool to identify the parasite state of T. gondii infection, allowing its application for diagnosis and epidemiological investigations in animals and humans. The identification of parasite infective stage can help to design effective strategies to minimize severe complications in immunocompromised people and, particularly, in pregnant women to prevent congenital infection.

Characterization of Toxoplasma DegP, a rhoptry serine protease crucial for lethal infection in mice.

Directory of Open Access Journals (Sweden)

Gaelle Lentini

Full Text Available During the infection process, Apicomplexa discharge their secretory organelles called micronemes, rhoptries and dense granules to sustain host cell invasion, intracellular replication and to modulate host cell pathways and immune responses. Herein, we describe the Toxoplasma gondii Deg-like serine protein (TgDegP, a rhoptry protein homologous to High temperature requirement A (HtrA or Deg-like family of serine proteases. TgDegP undergoes processing in both types I and II strains as most of the rhoptries proteins. We show that genetic disruption of the degP gene does not impact the parasite lytic cycle in vitro but affects virulence in mice. While in a type I strain DegPI appears dispensable for the establishment of an infection, removal of DegPII in a type II strain dramatically impairs the virulence. Finally, we show that KO-DegPII parasites kill immunodeficient mice as efficiently as the wild-type strain indicating that the protease might be involved in the complex crosstalk that the parasite engaged with the host immune response. Thus, this study unravels a novel rhoptry protein in T. gondii important for the establishment of lethal infection.

DMPD: Manipulation of mitogen-activated protein kinase/nuclear factor-kappaB-signalingcascades during intracellular Toxoplasma gondii infection. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 15361242 Manipulation of mitogen-activated protein kinase/nuclear factor-kappaB-sig...mmunol Rev. 2004 Oct;201:191-205. (.png) (.svg) (.html) (.csml) Show Manipulation of mitogen-activated prote... gondii infection. PubmedID 15361242 Title Manipulation of mitogen-activated protein kinase/nuclear factor-k

Evasion of Human Neutrophil-Mediated Host Defense during Toxoplasma gondii Infection.

Science.gov (United States)

Lima, Tatiane S; Gov, Lanny; Lodoen, Melissa B

2018-02-13

Neutrophils are a major player in host immunity to infection; however, the mechanisms by which human neutrophils respond to the intracellular protozoan parasite Toxoplasma gondii are still poorly understood. In the current study, we found that, whereas primary human monocytes produced interleukin-1beta (IL-1β) in response to T. gondii infection, human neutrophils from the same blood donors did not. Moreover, T. gondii inhibited lipopolysaccharide (LPS)-induced IL-1β synthesis in human peripheral blood neutrophils. IL-1β suppression required active parasite invasion, since heat-killed or mycalolide B-treated parasites did not inhibit IL-1β release. By investigating the mechanisms involved in this process, we found that T. gondii infection of neutrophils treated with LPS resulted in reduced transcript levels of IL-1β and NLRP3 and reduced protein levels of pro-IL-1β, mature IL-1β, and the inflammasome sensor NLRP3. In T. gondii -infected neutrophils stimulated with LPS, the levels of MyD88, TRAF6, IKKα, IKKβ, and phosphorylated IKKα/β were not affected. However, LPS-induced IκBα degradation and p65 phosphorylation were reduced in T. gondii- infected neutrophils, and degradation of IκBα was reversed by treatment with the proteasome inhibitor MG-132. Finally, we observed that T. gondii inhibited the cleavage and activity of caspase-1 in human neutrophils. These results indicate that T. gondii suppression of IL-1β involves a two-pronged strategy whereby T. gondii inhibits both NF-κB signaling and activation of the NLRP3 inflammasome. These findings represent a novel mechanism of T. gondii evasion of human neutrophil-mediated host defense by targeting the production of IL-1β. IMPORTANCE Toxoplasma gondii is an obligate intracellular parasite that infects approximately one-third of humans worldwide and can invade virtually any nucleated cell in the human body. Although it is well documented that neutrophils infiltrate the site of acute T. gondii

Overcoming T. gondii infection and intracellular protein nanocapsules as biomaterials for ultrasonically controlled drug release.

Science.gov (United States)

Aw, M S; Paniwnyk, L

2017-09-26

One of the pivotal matters of concern in intracellular drug delivery is the preparation of biomaterials containing drugs that are compatible with the host target. Nanocapsules for oral delivery are found to be suitable candidates for targeting Toxoplasma gondii (T. gondii), a maneuvering and smart protozoic parasite found across Europe and America that causes a subtle but deadly infection. To overcome this disease, there is much potential of integrating protein-based cells into bioinspired nanocompartments such as via biodegradable cross-linked disulfide polyelectrolyte nanoparticles. The inner membrane vesicle system of these protein-drugs is not as simple as one might think. It is a complex transport network that includes sequential pathways, namely, endocytosis, exocytosis and autophagy. Unfortunately, the intracellular trafficking routes for nanoparticles in cells have not been extensively and intensively investigated. Hence, there lies the need to create robust protein nanocapsules for precise tracing and triggering of drug release to combat this protozoic disease. Protein nanocapsules have the advantage over other biomaterials due to their biocompatibility, use of natural ingredients, non-invasiveness, patient compliance, cost and time effectiveness. They also offer low maintenance, non-toxicity to healthy cells and a strictly defined route toward intracellular elimination through controlled drug delivery within the therapeutic window. This review covers the unprecedented opportunities that exist for constructing advanced nanocapsules to meet the growing needs arising from many therapeutic fields. Their versatile use includes therapeutic ultrasound for tumor imaging, recombinant DNA, ligand and functional group binding, the delivery of drugs and peptides via protein nanocapsules and polyelectrolytes, ultrasound-(US)-aided drug release through the gastrointestinal (GI) tract, and the recent progress in targeting tumor cells and a vast range of cancer therapies

Long-Term Protective Immune Response Elicited by Vaccination with an Expression Genomic Library of Toxoplasma gondii

OpenAIRE

Fachado, Alberto; Rodriguez, Alexandro; Molina, Judith; Silvério, Jaline C.; Marino, Ana P. M. P.; Pinto, Luzia M. O.; Angel, Sergio O.; Infante, Juan F.; Traub-Cseko, Yara; Amendoeira, Regina R.; Lannes-Vieira, Joseli

2003-01-01

Immunization of BALB/c mice with an expression genomic library of Toxoplasma gondii induces a Th1-type immune response, with recognition of several T. gondii proteins (21 to 117 kDa) and long-term protective immunity against a lethal challenge. These results support further investigations to achieve a multicomponent anti-T. gondii DNA vaccine.

Effects of dendritic cell vaccine activated with protein components of toxoplasma gondii on tumor specific CD8+ T-cells

Directory of Open Access Journals (Sweden)

Amari A

2009-12-01

Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Dendritic Cell (DC is an important antigen-presenting cell that present tumor antigen to CD8+ and CD4+ T- Lymphocytes and induce specific anti-tumor immunity. In order to induce effective anti-tumor response, an option is increasing the efficiency of antigen presentation of dendritic cells and T cell activation capacity. The aim of the present study was to investigate the effect of dendritic cell maturation with protein components of toxoplasma gondii on cytotoxic T lymphocyte activity and their infiltration in to the tumor."n"nMethods: For DC generation, bone marrow cells were cultured in the presence of GM-CSF and IL-4 for five days. After that, LPS, protein components and whole extract of toxoplasma gondii were added to the culture media and incubated for another two days for DC maturation. To generate tumor, mices were injected subcutaneously with WEHI-164 cell line. For immunotherapy 106 DCs matured with different compounds were injected around the tumor site. Infiltration of CD8+ T cells were determined by flow cytometry and cytotoxic activity was measured by LDH detection kit."n"nResults: Immunotherapy with DCs treated with protein components of toxoplasma gondii led to a significant increase in the

Taxonomy Icon Data: Toxoplasma gondii [Taxonomy Icon

Lifescience Database Archive (English)

Full Text Available Toxoplasma gondii Toxoplasma gondii Toxoplasma_gondii_L.png Toxoplasma_gondii_NL.png Toxoplasma..._gondii_S.png Toxoplasma_gondii_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Toxoplasma...+gondii&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Toxoplasma+gondii&t=NL http://biosciencedbc.j...p/taxonomy_icon/icon.cgi?i=Toxoplasma+gondii&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Toxoplas...ma+gondii&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=113 ...

Global iTRAQ-based proteomic profiling of Toxoplasma gondii oocysts during sporulation.

Science.gov (United States)

Zhou, Chun-Xue; Zhu, Xing-Quan; Elsheikha, Hany M; He, Shuai; Li, Qian; Zhou, Dong-Hui; Suo, Xun

2016-10-04

Toxoplasma gondii is a medically and economically important protozoan parasite. However, the molecular mechanisms of its sporulation remain largely unknown. Here, we applied iTRAQ coupled with 2D LC-MS/MS proteomic analysis to investigate the proteomic expression profile of T. gondii oocysts during sporulation. Of the 2095 non-redundant proteins identified, 587 were identified as differentially expressed proteins (DEPs). Based on Gene Ontology enrichment and KEGG pathway analyses the majority of these DEPs were found related to the metabolism of amino acids, carbon and energy. Protein interaction network analysis generated by STRING identified ATP-citrate lyase (ACL), GMP synthase, IMP dehydrogenase (IMPDH), poly (ADP-ribose) glycohydrolase (PARG), and bifunctional dihydrofolate reductase-thymidylate synthase (DHFR-TS) as the top five hubs. We also identified 25 parasite virulence factors that were expressed at relatively high levels in sporulated oocysts compared to non-sporulated oocysts, which might contribute to the infectivity of mature oocysts. Considering the importance of oocysts in the dissemination of toxoplasmosis these findings may help in the search of protein targets with a key role in infectiousness and ecological success of oocysts, creating new opportunities for the development of better means for disease prevention. The development of new preventative interventions against T. gondii infection relies on an improved understanding of the proteome and chemical pathways of this parasite. To identify proteins required for the development of environmentally resistant and infective T. gondii oocysts, we compared the proteome of non-sporulated (immature) oocysts with the proteome of sporulated (mature, infective) oocysts. iTRAQ 2D-LC-MS/MS analysis revealed proteomic changes that distinguish non-sporulated from sporulated oocysts. Many of the differentially expressed proteins were involved in metabolic pathways and 25 virulence factors were identified

An in silico pipeline to filter the Toxoplasma gondii proteome for proteins that could traffic to the host cell nucleus and influence host cell epigenetic regulation.

Science.gov (United States)

Syn, Genevieve; Blackwell, Jenefer M; Jamieson, Sarra E; Francis, Richard W

2018-01-01

Toxoplasma gondii uses epigenetic mechanisms to regulate both endogenous and host cell gene expression. To identify genes with putative epigenetic functions, we developed an in silico pipeline to interrogate the T. gondii proteome of 8313 proteins. Step 1 employs PredictNLS and NucPred to identify genes predicted to target eukaryotic nuclei. Step 2 uses GOLink to identify proteins of epigenetic function based on Gene Ontology terms. This resulted in 611 putative nuclear localised proteins with predicted epigenetic functions. Step 3 filtered for secretory proteins using SignalP, SecretomeP, and experimental data. This identified 57 of the 611 putative epigenetic proteins as likely to be secreted. The pipeline is freely available online, uses open access tools and software with user-friendly Perl scripts to automate and manage the results, and is readily adaptable to undertake any such in silico search for genes contributing to particular functions.

A Toxoplasma gondii protein with homology to intracellular type Na+/H+ exchangers is important for osmoregulation and invasion

International Nuclear Information System (INIS)

Francia, Maria E.; Wicher, Sarah; Pace, Douglas A.; Sullivan, Jack; Moreno, Silvia N.J.; Arrizabalaga, Gustavo

2011-01-01

The obligate intracellular parasite Toxoplasma gondii is exposed to a variety of physiological conditions while propagating in an infected organism. The mechanisms by which Toxoplasma overcomes these dramatic changes in its environment are not known. In yeast and plants, ion detoxification and osmotic regulation are controlled by vacuolar compartments. A novel compartment named the plant-like vacuole or vacuolar compartment (PLV/VAC) has recently been described in T.gondii, which could potentially protect extracellular tachyzoites against salt and other ionic stresses. Here, we report the molecular characterization of the vacuolar type Na + /H + exchanger in T. gondii, TgNHE3, and its co-localization with the PLV/VAC proton-pyrophosphatase (TgVP1). We have created a TgNHE3 knockout strain, which is more sensitive to hyperosmotic shock and toxic levels of sodium, possesses a higher intracellular Ca 2+ concentration [Ca 2+ ] i , and exhibits a reduced host invasion efficiency. The defect in invasion correlates with a measurable reduction in the secretion of the adhesin TgMIC2. Overall, our results suggest that the PLV/VAC has functions analogous to those of the vacuolar compartments of plants and yeasts, providing the parasite with a mechanism to resist ionic fluctuations and, potentially, regulate protein trafficking.

Purification, crystallization and preliminary X-ray diffraction analysis of inner membrane complex (IMC) subcompartment protein 1 (ISP1) from Toxoplasma gondii

International Nuclear Information System (INIS)

Tonkin, Michelle L.; Brown, Shannon; Beck, Josh R.; Bradley, Peter J.; Boulanger, Martin J.

2012-01-01

To characterize the ISP family of proteins present in apicomplexan parasites, ISP1 from T. gondii was expressed, purified and crystallized. Two crystal forms (cubic and orthorhombic) were analyzed by X-ray diffraction and data were processed to 2.05 and 2.1 Å resolution, respectively. The protozoan parasites of the Apicomplexa phylum are devastating global pathogens. Their success is largely due to phylum-specific proteins found in specialized organelles and cellular structures. The inner membrane complex (IMC) is a unique apicomplexan structure that is essential for motility, invasion and replication. The IMC subcompartment proteins (ISP) have recently been identified in Toxoplasma gondii and shown to be critical for replication, although their specific mechanisms are unknown. Structural characterization of TgISP1 was pursued in order to identify the fold adopted by the ISPs and to generate detailed insight into how this family of proteins functions during replication. An N-terminally truncated form of TgISP1 was purified from Escherichia coli, crystallized and subjected to X-ray diffraction analysis. Two crystal forms of TgISP1 belonging to space groups P4 1 32 or P4 3 32 and P2 1 2 1 2 1 diffracted to 2.05 and 2.1 Å resolution, respectively

Identification of a dithiol-dependent nucleoside triphosphate hydrolase in Sarcocystis neurona.

Science.gov (United States)

Zhang, Deqing; Gaji, Rajshekhar Y; Howe, Daniel K

2006-09-01

A putative nucleoside triphosphate hydrolase (NTPase) gene was identified in a database of expressed sequence tags (ESTs) from the apicomplexan parasite Sarcocystis neurona. Analysis of culture-derived S. neurona merozoites demonstrated a dithiol-dependent NTPase activity, consistent with the presence of a homologue to the TgNTPases of Toxoplasma gondii. A complete cDNA was obtained for the S. neurona gene and the predicted amino acid sequence shared 38% identity with the two TgNTPase isoforms from T. gondii. Based on the obvious homology, the S. neurona protein was designated SnNTP1. The SnNTP1 cDNA encodes a polypeptide of 714 amino acids with a predicted 22-residue signal peptide and an estimated mature molecular mass of 70kDa. Southern blot analysis of the SnNTP1 locus revealed that the gene exists as a single copy in the S. neurona genome, unlike the multiple gene copies that have been observed in T. gondii and Neospora caninum. Analyses of the SnNTP1 protein demonstrated that it is soluble and secreted into the culture medium by extracellular merozoites. Surprisingly, indirect immunofluorescence analysis of intracellular S. neurona revealed apical localisation of SnNTP1 and temporal expression characteristics that are comparable with the microneme protein SnMIC10. The absence of SnNTP1 during much of endopolygeny implies that this protein does not serve a function during intracellular growth and development of S. neurona schizonts. Instead, SnNTP1 may play a role in events that occur during or proximal to merozoite egress from and/or invasion into cells.

Toxoplasma gondii and schizophrenia

OpenAIRE

Mokhtari Mohammadreza; Mokhtari Mojgan

2006-01-01

Recent epidemiologic studies indicate that infectious agents may contribute to some cases of schizophrenia. In animals, infection with Toxoplasma gondii can alter behavior and neurotransmitter function. In humans, acute infection with T. gondii can produce psychotic symptoms similar to those displayed by persons with schizophrenia. Since 1953, a total of 19 studies of T. gondii antibodies in persons with schizophrenia and other severe psychiatric disorders and in controls have been reported; ...

Towards vaccine against toxoplasmosis: evaluation of the immunogenic and protective activity of recombinant ROP5 and ROP18 Toxoplasma gondii proteins.

Science.gov (United States)

Grzybowski, Marcin M; Dziadek, Bożena; Gatkowska, Justyna M; Dzitko, Katarzyna; Długońska, Henryka

2015-12-01

Toxoplasmosis is one of the most common parasitic infections worldwide. An effective vaccine against human and animal toxoplasmosis is still needed to control this parasitosis. The polymorphic rhoptry proteins, ROP5 and ROP18, secreted by Toxoplasma gondii during the invasion of the host cell have been recently considered as promising vaccine antigens, as they appear to be the major determinants of T. gondii virulence in mice. The goal of this study was to evaluate their immunogenic and immunoprotective activity after their administration (separately or both recombinant proteins together) with the poly I:C as an adjuvant. Immunization of BALB/c and C3H/HeOuJ mice generated both cellular and humoral specific immune responses with some predominance of IgG1 antibodies. The spleen cells derived from vaccinated animals reacted to the parasite's native antigens. Furthermore, the immunization led to a partial protection against acute and chronic toxoplasmosis. These findings confirm the previous assumptions about ROP5 and ROP18 antigens as valuable components of a subunit vaccine against toxoplasmosis.

The Inner Membrane Complex Sub-compartment Proteins Critical for Replication of the Apicomplexan Parasite Toxoplasma gondii Adopt a Pleckstrin Homology Fold*

Science.gov (United States)

Tonkin, Michelle L.; Beck, Josh R.; Bradley, Peter J.; Boulanger, Martin J.

2014-01-01

Toxoplasma gondii, an apicomplexan parasite prevalent in developed nations, infects up to one-third of the human population. The success of this parasite depends on several unique structures including an inner membrane complex (IMC) that lines the interior of the plasma membrane and contains proteins important for gliding motility and replication. Of these proteins, the IMC sub-compartment proteins (ISPs) have recently been shown to play a role in asexual T. gondii daughter cell formation, yet the mechanism is unknown. Complicating mechanistic characterization of the ISPs is a lack of sequence identity with proteins of known structure or function. In support of elucidating the function of ISPs, we first determined the crystal structures of representative members TgISP1 and TgISP3 to a resolution of 2.10 and 2.32 Å, respectively. Structural analysis revealed that both ISPs adopt a pleckstrin homology fold often associated with phospholipid binding or protein-protein interactions. Substitution of basic for hydrophobic residues in the region that overlays with phospholipid binding in related pleckstrin homology domains, however, suggests that ISPs do not retain phospholipid binding activity. Consistent with this observation, biochemical assays revealed no phospholipid binding activity. Interestingly, mapping of conserved surface residues combined with crystal packing analysis indicates that TgISPs have functionally repurposed the phospholipid-binding site likely to coordinate protein partners. Recruitment of larger protein complexes may also be aided through avidity-enhanced interactions resulting from multimerization of the ISPs. Overall, we propose a model where TgISPs recruit protein partners to the IMC to ensure correct progression of daughter cell formation. PMID:24675080

Interaction and cystogenesis of Toxoplasma gondii within skeletal muscle cells in vitro

Directory of Open Access Journals (Sweden)

Erick Vaz Guimarães

2009-03-01

Full Text Available Infection by the protozoan parasite Toxoplasma gondii is widely prevalent in humans and animals. To prevent human infection, all meat should be well cooked before consumption, since the parasite is present in skeletal muscle. In this context, the use of skeletal muscle cells (SkMCs as a cellular model opens up new approaches to investigate T. gondii-host cell interactions. Immunofluorescent detection of proteins that are stage-specific for bradyzoites indicated that complete cystogenesis of T. gondii in in vitro cultures of SkMCs occurs after 96 h of infection. Ultrastructural analysis showed that, after 48 h of interaction, there were alterations on the parasitophorous vacuole membrane, including greater thickness and increased electron density at the inner face of the membrane. The present study demonstrates the potential use of primary cultures of SkMCs to evaluate different molecular aspects of T. gondii invasion and cystogenesis and presents a promising in vitro model for the screening of drug activities toward tissue cysts and bradyzoites.

Evaluation of Protective Immune Responses Induced by Recombinant TrxLp and ENO2 Proteins against Toxoplasma gondii Infection in BALB/c Mice

Directory of Open Access Journals (Sweden)

Meng Wang

2016-01-01

Full Text Available Toxoplasma gondii is an obligate intracellular parasitic protozoan that can infect almost all species of warm-blooded animals. As any chemical-based drugs could not act against the tissue cyst stage of T. gondii, vaccination may be one of the ideal control strategies. In the present study, two new vaccine candidates, named TgENO2 and TgTrxLp, were purified from Escherichia coli with pET-30a(+ expression system and then were injected into BALB/c mice to evaluate the protective efficacy against acute and chronic toxoplasmosis. The results showed that both the recombinant proteins, either alone or in combination, could elicit strong humoral and cellular immune responses with a higher level of IgG antibodies, IFN-γ, IL-2, CD4+, and CD8+ T cells as compared to those in mice from control groups. After acute challenge with tachyzoites of the GJS strain, mice immunized with rTgTrxLp (8±2.77 d, rTgENO2 (7.4±1.81 d, and rTgTrxLp + rTgENO2 (8.38±4.57 d proteins showed significantly longer survival time than those that received Freund’s adjuvant (6.78±2.08 d and PBS (6.38±4.65 d (χ2 = 9.687, df = 4, P=0.046. The protective immunity of rTgTrxLp, rTgENO2, and rTgTrxLp + rTgENO2 proteins against chronic T. gondii infection showed 69.77%, 58.14%, and 20.93% brain cyst reduction as compared to mice that received PBS. The present study suggested that both TgENO2 and TgTrxLp were potential candidates for the development of multicomponent vaccines against toxoplasmosis.

Toxoplasma gondii Infection Is Associated with Mitochondrial Dysfunction in-Vitro

Directory of Open Access Journals (Sweden)

Genevieve Syn

2017-12-01

Full Text Available Upon invasion of host cells, the ubiquitous pathogen Toxoplasma gondii manipulates several host processes, including re-organization of host organelles, to create a replicative niche. Host mitochondrial association to T. gondii parasitophorous vacuoles is rapid and has roles in modulating host immune responses. Here gene expression profiling of T. gondii infected cells reveals enrichment of genes involved in oxidative phosphorylation (OXPHOS and mitochondrial dysfunction 6 h post-infection. We identified 11 hub genes (HIF-1α, CASP8, FN1, POU5F1, CD44, ISG15, HNRNPA1, MDM2, RPL35, VHL, and NUPR1 and 10 predicted upstream regulators, including 4 endogenous regulators RICTOR, KDM5A, RB1, and D-glucose. We characterized a number of mitochondrial parameters in T. gondii infected human foreskin fibroblast cells over a 36 h time-course. In addition to the usual rapid recruitment and apparent enlargement of mitochondria around the parasitophorous vacuole we observed fragmented host mitochondria in infected cells, not linked to cellular apoptosis, from 24 h post-infection. An increase in mitochondrial superoxide levels in T. gondii infected cells was observed that required active parasite invasion and peaked at 30 h post-infection. Measurement of OXPHOS proteins showed decreased expression of Complex IV in infected cells at 24 h post-infection, followed by decreased expression of Complexes I and II at 36 h post-infection. No change occurred in Complex V. No difference in host mitochondrial membrane potential between infected and mock-infected cells was observed at any time. Our results show perturbation of host mitochondrial function following T. gondii infection that likely impacts on pathogenesis of disease.

Dual Identification and Analysis of Differentially Expressed Transcripts of Porcine PK-15 Cells and Toxoplasma gondii during in vitro Infection

Directory of Open Access Journals (Sweden)

Chun-Xue eZhou

2016-05-01

Full Text Available Toxoplasma gondii is responsible for causing toxoplasmosis, one of the most prevalent zoonotic parasitoses worldwide. The mechanisms that mediate T. gondii infection of pigs (the most common source of human infection and renal tissues are still unknown. To identify the critical alterations that take place in the transcriptome of both porcine kidney (PK-15 cells and T. gondii following infection, infected cell samples were collected at 1, 3, 6, 9, 12, 18, and 24 h post infection and RNA-Seq data were acquired using Illumina Deep Sequencing. Differential Expression of Genes (DEGs analysis was performed to study the concomitant gene-specific temporal patterns of induction of mRNA expression of PK-15 cells and T. gondii. High sequence coverage enabled us to thoroughly characterize T. gondii transcriptome and identify the activated molecular pathways in host cells. More than 6G clean bases/ sample, including > 40 million clean reads were obtained. These were aligned to the reference genome of T. gondii and wild boar (Sus scrofa. DEGs involved in metabolic activities of T. gondii showed time-dependent down-regulation. However, DEGs involved in immune or disease related pathways of PK-15 cells peaked at 6 h PI, and were highly enriched as evidenced by KEGG analysis. Protein-protein interaction analysis revealed that TGME49_120110 (PCNA, TGME49_049180 (DHFR-TS, TGME49_055320 and TGME49_002300 (ITPase are the four hub genes with most interactions with T. gondii at the onset of infection. These results reveal altered profiles of gene expressed by PK-15 cells and T. gondii during infection and provide the groundwork for future virulence studies to uncover the mechanisms of T. gondii interaction with porcine renal tissue by functional analysis of these DEGs.

Toxoplasma gondii, Mental Health and Shizophrenia

Directory of Open Access Journals (Sweden)

Sibel Cevizci

2013-04-01

Full Text Available Protecting and promoting of mental health is one of the major application areas of public health. In particular, Toxoplasma gondii, which is a protozoal zoonosis common in Turkey, it is closely related to veterinary public health. In recent years, T.gondii can induce behavioral changes, may play a role in schizophrenia as an etiologic factor. Results of the recently performed studies shows that T.gondii may be a potential factor for some neuropathological changes in brain and suicide attemption. The purpose of this review is to present the data on recent epidemiology of T.gondii, mental health effects (changes in behavior, suicide, etc., the relationship between T.gondii and schizophrenia and offer some recommendations for protecting of public health. [TAF Prev Med Bull 2013; 12(2.000: 199-208

Hepatoprotective activity of Thymus vulgaris extract against Toxoplasma gondii infection

Directory of Open Access Journals (Sweden)

Nagwa Mostafa El-Sayed

2017-05-01

Full Text Available Objective: To evaluate the hepatoprotective activity of Thymus vulgaris (T. vulgaris extract against Toxoplasma gondii (T. gondii infection in experimentally infected mice. Methods: Sixty mice were divided into six groups (Group I–Group VI. Group I was normal control (non-infected, non-treated; Group II was non-infected and treated with T. vulgaris extract (500 mg/kg; Group III was T. gondii infected-non-immunosuppressed control; Group IV consisted of infected immunosuppressed mice; Group V was infected and treated with T. vulgaris extract; Group VI consisted of infected immunosuppressed mice treated with T. vulgaris extract. Hepatoprotective effect of T. vulgaris extract was evaluated by histopathological examination of tissue sections stained with hematoxylin and eosin, determination of liver function parameters (alanine aminotransaminase, aspartate aminotransaminase and alkaline phosphates, total bilirubin, total protein concentrations and assessment of hepatocytes genotoxicity by comet assay.Antigenotoxic effect of T. vulgaris was assessed by several comet assay parameters that were provided by the image analysis software, including % tailed cells, % of DNA in the tail, tail length, and tail moment. Results: Treatment with T. vulgaris in both Groups V and VI improved T. gondii induced pathological lesions in the infected liver that regressed to near the normal picture especially in Group V. Also, it restored the altered values of liver function parameters near to the normal levels significantly (P < 0.05 compared with Groups III and IV respectively. Regarding comet assay parameters, all of them were significantly increased (P < 0.05 after T. gondii infection (Group III and reached the greatest values in infected immunosuppressed group (Group IV compared to the normal controls (Group I. With treatment by T. vulgaris in Groups V and VI, there was a significant decrease (P < 0.05 in all values compared to Groups III and V respectively. The

The current status of Toxoplasma gondii infection among Egyptian rheumatoid arthritis patients

Directory of Open Access Journals (Sweden)

Nagwa Mostafa El-Sayed

2016-10-01

Full Text Available Objective: To ascertain a relationship between Toxoplasma gondii (T. gondii infection and rheumatoid arthritis (RA disease among Egyptian patients. Methods: One hundred RA patients and 50 healthy subjects participated in this study. The patients were classified into three groups, namely GI, G2 and G3. Patients in G1 were recently diagnosed with RA with the disease duration of less than one year (prior treatment; G2 included RA patients receiving anti-tumor necrosis factor agents and RA patients in G3 received disease modifying anti-rheumatic drugs (methotrexate, antimalarial, corticosteroids. Serum samples of all participants were examined for the presence of anti-Toxoplasma immunoglobulin G (IgG antibodies and positive samples were further analyzed for antiToxoplasma IgM antibodies to detect the possibility of reactivation of latent toxoplasmosis. Also, the association between Toxoplasma seropositivity and clinical, laboratory and radiological features of these patients were determined. Results: There was a significantly higher percentage of T. gondii IgG positivity in RA patients (54% than in the controls (32%. At the same time, 20.40% of T. gondii IgG positive patients had anti-T. gondii IgM antibodies with a statistically significant difference as comparing to T. gondii IgG positive controls. Out of T. gondii seropositive patients, 20.37% had a lower IgG level with a mean titer of (65.3 ± 17.7 IU/mL, 46.29% had moderate level with a mean titer of (184.2 ± 60.0 IU/mL and 33.33% had higher level with a mean titer of (404.3 ± 50.0 IU/ mL. A positive correlation was found between disease activity and Toxoplasma seropositivity. T. gondii seropositive RA patients had longer disease duration, longer time morning stiffness, higher numbers of tender and swollen joints and also increase in disease severity markers (erythrocyte sedimentation rate, C-reactive protein, disease activity score 28, anti-cyclic citrullinated peptide anti

Screening and identification of novel B cell epitopes of Toxoplasma gondii SAG1

OpenAIRE

Wang, Yanhua; Wang, Guangxiang; Zhang, Delin; Yin, Hong; Wang, Meng

2013-01-01

Background The identification of protein epitopes is useful for diagnostic purposes and for the development of peptide vaccines. In this study, the epitopes of Toxoplasma gondii SAG1 were identified using synthetic peptide techniques with the aid of bioinformatics. Findings Eleven peptides derived from T. gondii SAG1 were assessed by ELISA using pig sera from different time points after infection. Four (PS4, PS6, PS10 and PS11), out of the eleven peptides tested were recognized by all sera. T...

Sequence Variation in Toxoplasma gondii rop17 Gene among Strains from Different Hosts and Geographical Locations

Directory of Open Access Journals (Sweden)

Nian-Zhang Zhang

2014-01-01

Full Text Available Genetic diversity of T. gondii is a concern of many studies, due to the biological and epidemiological diversity of this parasite. The present study examined sequence variation in rhoptry protein 17 (ROP17 gene among T. gondii isolates from different hosts and geographical regions. The rop17 gene was amplified and sequenced from 10 T. gondii strains, and phylogenetic relationship among these T. gondii strains was reconstructed using maximum parsimony (MP, neighbor-joining (NJ, and maximum likelihood (ML analyses. The partial rop17 gene sequences were 1375 bp in length and A+T contents varied from 49.45% to 50.11% among all examined T. gondii strains. Sequence analysis identified 33 variable nucleotide positions (2.1%, 16 of which were identified as transitions. Phylogeny reconstruction based on rop17 gene data revealed two major clusters which could readily distinguish Type I and Type II strains. Analyses of sequence variations in nucleotides and amino acids among these strains revealed high ratio of nonsynonymous to synonymous polymorphisms (>1, indicating that rop17 shows signs of positive selection. This study demonstrated the existence of slightly high sequence variability in the rop17 gene sequences among T. gondii strains from different hosts and geographical regions, suggesting that rop17 gene may represent a new genetic marker for population genetic studies of T. gondii isolates.

Veterinary vaccines against Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Elisabeth A Innes

2009-03-01

Full Text Available Toxoplasma gondii has a very wide intermediate host range and is thought to be able to infect all warm blooded animals. The parasite causes a spectrum of different diseases and clinical symptoms within the intermediate hosts and following infection most animals develop adaptive humoral and cell-mediated immune responses. The development of protective immunity to T. gondii following natural infection in many host species has led researchers to look at vaccination as a strategy to control disease, parasite multiplication and establishment in animal hosts. A range of different veterinary vaccines are required to help control T. gondii infection which include vaccines to prevent congenital toxoplasmosis, reduce or eliminate tissue cysts in meat producing animals and to prevent oocyst shedding in cats. In this paper we will discuss some of the history, challenges and progress in the development of veterinary vaccines against T. gondii.

Seroprevalence of Toxoplasma gondii in Western Romania.

Science.gov (United States)

Olariu, Tudor Rares; Petrescu, Cristina; Darabus, Gheorghe; Lighezan, Rodica; Mazilu, Octavian

2015-08-01

Toxoplasma gondii is an obligate intracellular parasite that most commonly causes asymptomatic infection in immunocompetent hosts, but can have devastating consequences in congenitally infected infants and immunocompromised patients. We evaluated the seroprevalence of T. gondii in the general population in Western Romania. Sera from 304 individuals were analysed with the Pastorex Toxo test, which allows the simultaneous detection of T. gondii IgG and/or IgM antibodies. T. gondii antibodies were demonstrated in 197 individuals (64.8%) and the prevalence increased with age: 35.0% in those Romania.

Secretion of Rhoptry and Dense Granule Effector Proteins by Nonreplicating Toxoplasma gondii Uracil Auxotrophs Controls the Development of Antitumor Immunity.

Directory of Open Access Journals (Sweden)

Barbara A Fox

2016-07-01

Full Text Available Nonreplicating type I uracil auxotrophic mutants of Toxoplasma gondii possess a potent ability to activate therapeutic immunity to established solid tumors by reversing immune suppression in the tumor microenvironment. Here we engineered targeted deletions of parasite secreted effector proteins using a genetically tractable Δku80 vaccine strain to show that the secretion of specific rhoptry (ROP and dense granule (GRA proteins by uracil auxotrophic mutants of T. gondii in conjunction with host cell invasion activates antitumor immunity through host responses involving CD8α+ dendritic cells, the IL-12/interferon-gamma (IFN-γ TH1 axis, as well as CD4+ and CD8+ T cells. Deletion of parasitophorous vacuole membrane (PVM associated proteins ROP5, ROP17, ROP18, ROP35 or ROP38, intravacuolar network associated dense granule proteins GRA2 or GRA12, and GRA24 which traffics past the PVM to the host cell nucleus severely abrogated the antitumor response. In contrast, deletion of other secreted effector molecules such as GRA15, GRA16, or ROP16 that manipulate host cell signaling and transcriptional pathways, or deletion of PVM associated ROP21 or GRA3 molecules did not affect the antitumor activity. Association of ROP18 with the PVM was found to be essential for the development of the antitumor responses. Surprisingly, the ROP18 kinase activity required for resistance to IFN-γ activated host innate immunity related GTPases and virulence was not essential for the antitumor response. These data show that PVM functions of parasite secreted effector molecules, including ROP18, manipulate host cell responses through ROP18 kinase virulence independent mechanisms to activate potent antitumor responses. Our results demonstrate that PVM associated rhoptry effector proteins secreted prior to host cell invasion and dense granule effector proteins localized to the intravacuolar network and host nucleus that are secreted after host cell invasion coordinately

Seroprevalence of Toxoplasma gondii infection in Norwegian dairy goats

Directory of Open Access Journals (Sweden)

Stormoen Marit

2012-12-01

Full Text Available Abstract Background Toxoplasma gondii is a major problem for the sheep industry as it may cause reproduction problems. The importance of T. gondii in Norwegian goat herds is uncertain, but outbreaks of toxoplasmosis in dairy goat farms have been recorded. The aim of this study was to describe the prevalence of T. gondii infection in Norwegian dairy goats by using serology. Findings Goat serum originally collected as part of two nationwide surveillance and control programmes between 2002 and 2008 were examined for T. gondii antibodies by using direct agglutination test. In total, 55 of 73 herds (75% had one or more serologically positive animals, while 377 of 2188 (17% of the individual samples tested positive for T. gondii antibodies. Conclusions This is the first prevalence study of T. gondii infection in Norwegian goats. The results show that Norwegian goat herds are commonly exposed to T. gondii. Nevertheless, the majority of goat herds have a low prevalence of antibody positive animals, which make them vulnerable to infections with T. gondii during the gestation period.

Yeast three-hybrid screen identifies TgBRADIN/GRA24 as a negative regulator of Toxoplasma gondii bradyzoite differentiation.

Directory of Open Access Journals (Sweden)

Anahi V Odell

Full Text Available Differentiation of the protozoan parasite Toxoplasma gondii into its latent bradyzoite stage is a key event in the parasite's life cycle. Compound 2 is an imidazopyridine that was previously shown to inhibit the parasite lytic cycle, in part through inhibition of parasite cGMP-dependent protein kinase. We show here that Compound 2 can also enhance parasite differentiation, and we use yeast three-hybrid analysis to identify TgBRADIN/GRA24 as a parasite protein that interacts directly or indirectly with the compound. Disruption of the TgBRADIN/GRA24 gene leads to enhanced differentiation of the parasite, and the TgBRADIN/GRA24 knockout parasites show decreased susceptibility to the differentiation-enhancing effects of Compound 2. This study represents the first use of yeast three-hybrid analysis to study small-molecule mechanism of action in any pathogenic microorganism, and it identifies a previously unrecognized inhibitor of differentiation in T. gondii. A better understanding of the proteins and mechanisms regulating T. gondii differentiation will enable new approaches to preventing the establishment of chronic infection in this important human pathogen.

Toxoplasma gondii seroprevalence in breeding pigs in Estonia

DEFF Research Database (Denmark)

Santoro, Azzurra; Tagel, Maarja; Must, Kärt

2017-01-01

Background: Toxoplasma gondii is a widespread occurring parasite infecting warm-blooded animals, including pigs and humans. The aims of this study were to estimate the prevalence of anti-T. gondii antibodies and to evaluate risk factors for T. gondii seropositivity in breeding pigs raised in Esto...

Toxoplasma gondii GRA7-Targeted ASC and PLD1 Promote Antibacterial Host Defense via PKCα.

Science.gov (United States)

Koh, Hyun-Jung; Kim, Ye-Ram; Kim, Jae-Sung; Yun, Jin-Seung; Jang, Kiseok; Yang, Chul-Su

2017-01-01

Tuberculosis is a global health problem and at least one-third of the world's population is infected with Mycobacterium tuberculosis (MTB). MTB is a successful pathogen that enhances its own intracellular survival by inhibiting inflammation and arresting phago-lysosomal fusion. We previously demonstrated that Toxoplasma gondii (T. gondii) dense granule antigen (GRA) 7 interacts with TNF receptor-associated factor 6 via Myeloid differentiation primary response gene 88, enabling innate immune responses in macrophages. To extend these studies, we found that GRA7 interacts with host proteins involved in antimicrobial host defense mechanisms as a therapeutic strategy for tuberculosis. Here, we show that protein kinase C (PKC)α-mediated phosphorylation of T. gondii GRA7-I (Ser52) regulates the interaction of GRA7 with PYD domain of apoptosis-associated speck-like protein containing a carboxy-terminal CARD, which is capable of oligomerization and inflammasome activation can lead to antimicrobial defense against MTB. Furthermore, GRA7-III interacted with the PX domain of phospholipase D1, facilitating its enzyme activity, phago-lysosomal maturation, and subsequent antimicrobial activity in a GRA7-III (Ser135) phosphorylation-dependent manner via PKCα. Taken together, these results underscore a previously unrecognized role of GRA7 in modulating antimicrobial host defense mechanism during mycobacterial infection.

Toxoplasma gondii GRA7-Targeted ASC and PLD1 Promote Antibacterial Host Defense via PKCα.

Directory of Open Access Journals (Sweden)

Hyun-Jung Koh

2017-01-01

Full Text Available Tuberculosis is a global health problem and at least one-third of the world's population is infected with Mycobacterium tuberculosis (MTB. MTB is a successful pathogen that enhances its own intracellular survival by inhibiting inflammation and arresting phago-lysosomal fusion. We previously demonstrated that Toxoplasma gondii (T. gondii dense granule antigen (GRA 7 interacts with TNF receptor-associated factor 6 via Myeloid differentiation primary response gene 88, enabling innate immune responses in macrophages. To extend these studies, we found that GRA7 interacts with host proteins involved in antimicrobial host defense mechanisms as a therapeutic strategy for tuberculosis. Here, we show that protein kinase C (PKCα-mediated phosphorylation of T. gondii GRA7-I (Ser52 regulates the interaction of GRA7 with PYD domain of apoptosis-associated speck-like protein containing a carboxy-terminal CARD, which is capable of oligomerization and inflammasome activation can lead to antimicrobial defense against MTB. Furthermore, GRA7-III interacted with the PX domain of phospholipase D1, facilitating its enzyme activity, phago-lysosomal maturation, and subsequent antimicrobial activity in a GRA7-III (Ser135 phosphorylation-dependent manner via PKCα. Taken together, these results underscore a previously unrecognized role of GRA7 in modulating antimicrobial host defense mechanism during mycobacterial infection.

Export of a Toxoplasma gondii rhoptry neck protein complex at the host cell membrane to form the moving junction during invasion.

Directory of Open Access Journals (Sweden)

Sébastien Besteiro

2009-02-01

Full Text Available One of the most conserved features of the invasion process in Apicomplexa parasites is the formation of a moving junction (MJ between the apex of the parasite and the host cell membrane that moves along the parasite and serves as support to propel it inside the host cell. The MJ was, up to a recent period, completely unknown at the molecular level. Recently, proteins originated from two distinct post-Golgi specialised secretory organelles, the micronemes (for AMA1 and the neck of the rhoptries (for RON2/RON4/RON5 proteins, have been shown to form a complex. AMA1 and RON4 in particular, have been localised to the MJ during invasion. Using biochemical approaches, we have identified RON8 as an additional member of the complex. We also demonstrated that all RON proteins are present at the MJ during invasion. Using metabolic labelling and immunoprecipitation, we showed that RON2 and AMA1 were able to interact in the absence of the other members. We also discovered that all MJ proteins are subjected to proteolytic maturation during trafficking to their respective organelles and that they could associate as non-mature forms in vitro. Finally, whereas AMA1 has previously been shown to be inserted into the parasite membrane upon secretion, we demonstrated, using differential permeabilization and loading of RON-specific antibodies into the host cell, that the RON complex is targeted to the host cell membrane, where RON4/5/8 remain associated with the cytoplasmic face. Globally, these results point toward a model of MJ organization where the parasite would be secreting and inserting interacting components on either side of the MJ, both at the host and at its own plasma membranes.

Toxoplasma gondii exposure and Parkinson's disease: a case–control study

Science.gov (United States)

Alvarado-Esquivel, Cosme; Méndez-Hernández, Edna Madai; Salas-Pacheco, José Manuel; Ruano-Calderón, Luis Ángel; Hernández-Tinoco, Jesús; Arias-Carrión, Oscar; Sánchez-Anguiano, Luis Francisco; Castellanos-Juárez, Francisco Xavier; Sandoval-Carrillo, Ada Agustina; Liesenfeld, Oliver; Ramos-Nevárez, Agar

2017-01-01

Objectives To determine the association between Toxoplasma gondii infection and Parkinson's disease and to investigate whether T. gondii seropositivity is associated with the general characteristics of patients with Parkinson's disease. Design Case–control study. Setting Cases and controls were enrolled in Durango City, Mexico. Participants 65 patients with Parkinson's disease and 195 age- and gender-matched control subjects without Parkinson's disease. Primary and secondary outcome measures Serum samples of participants were analysed for anti-T. gondii IgG and IgM antibodies by commercially available enzyme-linked immunoassays. Prevalence of T. gondii DNA was determined in seropositive subjects using PCR. The association between clinical data and infection was examined by bivariate analysis. Results Anti-T. gondii IgG antibodies were found in 6/65 cases (9.2%) and in 21/195 controls (10.8%) (OR 0.84; 95% CI 0.32 to 2.18; p=0.81). The frequency of high (>150 IU/mL) antibody levels was similar among cases and controls (p=0.34). None of the anti-T. gondii IgG positive cases and four of the anti-T. gondii IgG positive controls had anti-T. gondii IgM antibodies (p=0.54). The prevalence of T. gondii DNA was comparable in seropositive cases and controls (16.7% and 25%, respectively; p=1.0). Seroprevalence of T. gondii infection was associated with a young age onset of disease (p=0.03), high Unified Parkinson Disease Rating Scale scores (p=0.04) and depression (p=0.02). Seropositivity to T. gondii infection was lower in patients treated with pramipexole than in patients without this treatment (p=0.01). However, none of the associations remained significant after Bonferroni correction. Conclusions The results do not support an association between T. gondii infection and Parkinson's disease. However, T. gondii infection might have an influence on certain symptoms of Parkinson's disease. Further research to elucidate the role of T. gondii exposure on Parkinson's disease

Identification and characterization of secreted proteins in Eimeria tenella

Science.gov (United States)

Ramlee, Intan Azlinda; Firdaus-Raih, Mohd; Wan, Kiew-Lian

2015-09-01

Eimeria tenella is a protozoan parasite that causes coccidiosis, an economically important disease in the poultry industry. The characterization of proteins that are secreted by parasites have been shown to play important roles in parasite invasion and are considered to be potential control agents. In this study, 775 proteins potentially secreted by E. tenella were identified. These proteins were further filtered to remove mitochondrial proteins. Out of 763 putative secreted proteins, 259 proteins possess transmembrane domains while another 150 proteins have GPI (Glycosylphosphatidylinositol) anchors. Homology search revealed that 315 and 448 proteins have matches with known and hypothetical proteins in the database, respectively. Within this data set, previously characterized secretory proteins such as micronemes, rhoptry kinases and dense granules were detected.

Screening and identification of novel B cell epitopes of Toxoplasma gondii SAG1.

Science.gov (United States)

Wang, Yanhua; Wang, Guangxiang; Zhang, Delin; Yin, Hong; Wang, Meng

2013-04-30

The identification of protein epitopes is useful for diagnostic purposes and for the development of peptide vaccines. In this study, the epitopes of Toxoplasma gondii SAG1 were identified using synthetic peptide techniques with the aid of bioinformatics. Eleven peptides derived from T. gondii SAG1 were assessed by ELISA using pig sera from different time points after infection. Four (PS4, PS6, PS10 and PS11), out of the eleven peptides tested were recognized by all sera. Then, shorter peptides that were derived from PS4, PS6, PS10 and PS11 were predicted using bioinformatics and tested by experimentation. Four out of nine shorter peptides were identified successfully (amino acids 106-120, 166-180, 289-300 and 313-332). We have precisely located the epitopes of T. gondii SAG1 using pig sera collected at different time points after infection. The identified epitopes may be useful for the further study of epitope-based vaccines and diagnostic reagents.

Toxoplasma gondii actively inhibits neuronal function in chronically infected mice.

Directory of Open Access Journals (Sweden)

Fahad Haroon

Full Text Available Upon infection with the obligate intracellular parasite Toxoplasma gondii, fast replicating tachyzoites infect a broad spectrum of host cells including neurons. Under the pressure of the immune response, tachyzoites convert into slow-replicating bradyzoites, which persist as cysts in neurons. Currently, it is unclear whether T. gondii alters the functional activity of neurons, which may contribute to altered behaviour of T. gondii-infected mice and men. In the present study we demonstrate that upon oral infection with T. gondii cysts, chronically infected BALB/c mice lost over time their natural fear against cat urine which was paralleled by the persistence of the parasite in brain regions affecting behaviour and odor perception. Detailed immunohistochemistry showed that in infected neurons not only parasitic cysts but also the host cell cytoplasm and some axons stained positive for Toxoplasma antigen suggesting that parasitic proteins might directly interfere with neuronal function. In fact, in vitro live cell calcium (Ca(2+ imaging studies revealed that tachyzoites actively manipulated Ca(2+ signalling upon glutamate stimulation leading either to hyper- or hypo-responsive neurons. Experiments with the endoplasmatic reticulum Ca(2+ uptake inhibitor thapsigargin indicate that tachyzoites deplete Ca(2+ stores in the endoplasmatic reticulum. Furthermore in vivo studies revealed that the activity-dependent uptake of the potassium analogue thallium was reduced in cyst harbouring neurons indicating their functional impairment. The percentage of non-functional neurons increased over time In conclusion, both bradyzoites and tachyzoites functionally silence infected neurons, which may significantly contribute to the altered behaviour of the host.

AN EVALUATION STUDY OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA USING RECOMBINANT PROTEIN GRA1 FOR DETECTION OF IGG ANTIBODIES AGAINTS TOXOPLASMA GONDII INFECTIONS

Directory of Open Access Journals (Sweden)

Nina Difla Muflikhah

2017-08-01

Full Text Available Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an intracellular protozoan parasite that live inside the cells of the reticulo endothelial and parenchymal cells of human and animals (mammals and birds. Some cases of toxoplasmosis usually have no symptoms, but in any cases caused severe symptoms, such as hydrocephalus, microcephalus, intracranial calcification, retinal damage, brain abscess, mental retardation, lymphadenopathy, and others. Its severe symptoms usually showed a long time after first exposure, except symptoms showed by congenital transmission caused by infected mother. Early diagnosis is important to prevent the illness but methods for toxoplasmosis screening are still too expensive for developing country. Enzyme-linked immunosorbent assay (ELISA allow the testing of a large number samples within short time frame and based on antibody or antigen detection. This study aimed to know the sensitivity and specificity of recombinat protein GRA1 as antigen using ELISA methods. We tested the sensitivity and spesificity of GRA1 protein as antigen in ELISA methods to diagnose toxoplasmosis and compared with ELISA Kit Commercial. Reliable laboratory testing is important to detect Toxoplasma gondii infection, and focused to improving the low cost and easy-to-use diagnostic instrument. Seventy sera collected and tested using both indirect ELISA, commercial ELISA kit and GRA1 protein coated as antigen. Fourty eight and fifty one samples showed positive IgG antibody result of ELISA-GRA1 and ELISA kit. Negative sample tested by ELISA-GRA1 was 22 samples and 19 sample tested by ELISA Kit. The sensitivity and specificity of GRA1-based on ELISA were 100% and 86.36%, positive prediction value (ppv was 94.11%. These data indicate that the recombinant protein GRA1 is a highly immunogenic protein in human toxoplasmosis and become a promising marker for the screening of toxoplasmosis.

Host Mitochondrial Association Evolved in the Human Parasite Toxoplasma gondii via Neofunctionalization of a Gene Duplicate.

Science.gov (United States)

Adomako-Ankomah, Yaw; English, Elizabeth D; Danielson, Jeffrey J; Pernas, Lena F; Parker, Michelle L; Boulanger, Martin J; Dubey, Jitender P; Boyle, Jon P

2016-05-01

In Toxoplasma gondii, an intracellular parasite of humans and other animals, host mitochondrial association (HMA) is driven by a gene family that encodes multiple mitochondrial association factor 1 (MAF1) proteins. However, the importance of MAF1 gene duplication in the evolution of HMA is not understood, nor is the impact of HMA on parasite biology. Here we used within- and between-species comparative analysis to determine that the MAF1 locus is duplicated in T. gondii and its nearest extant relative Hammondia hammondi, but not another close relative, Neospora caninum Using cross-species complementation, we determined that the MAF1 locus harbors multiple distinct paralogs that differ in their ability to mediate HMA, and that only T. gondii and H. hammondi harbor HMA(+) paralogs. Additionally, we found that exogenous expression of an HMA(+) paralog in T. gondii strains that do not normally exhibit HMA provides a competitive advantage over their wild-type counterparts during a mouse infection. These data indicate that HMA likely evolved by neofunctionalization of a duplicate MAF1 copy in the common ancestor of T. gondii and H. hammondi, and that the neofunctionalized gene duplicate is selectively advantageous. Copyright © 2016 by the Genetics Society of America.

Metabolic Cooperation of Glucose and Glutamine Is Essential for the Lytic Cycle of Obligate Intracellular Parasite Toxoplasma gondii*

OpenAIRE

Nitzsche, Richard; Zagoriy, Vyacheslav; Lucius, Richard; Gupta, Nishith

2015-01-01

Toxoplasma gondii is a widespread protozoan parasite infecting nearly all warm-blooded organisms. Asexual reproduction of the parasite within its host cells is achieved by consecutive lytic cycles, which necessitates biogenesis of significant energy and biomass. Here we show that glucose and glutamine are the two major physiologically important nutrients used for the synthesis of macromolecules (ATP, nucleic acid, proteins, and lipids) in T. gondii, and either of them is sufficient to ensure ...

Diagnosis of toxoplasmosis and typing of Toxoplasma gondii.

Science.gov (United States)

Liu, Quan; Wang, Ze-Dong; Huang, Si-Yang; Zhu, Xing-Quan

2015-05-28

Toxoplasmosis, caused by the obligate intracellular protozoan Toxoplasma gondii, is an important zoonosis with medical and veterinary importance worldwide. The disease is mainly contracted by ingesting undercooked or raw meat containing viable tissue cysts, or by ingesting food or water contaminated with oocysts. The diagnosis and genetic characterization of T. gondii infection is crucial for the surveillance, prevention and control of toxoplasmosis. Traditional approaches for the diagnosis of toxoplasmosis include etiological, immunological and imaging techniques. Diagnosis of toxoplasmosis has been improved by the emergence of molecular technologies to amplify parasite nucleic acids. Among these, polymerase chain reaction (PCR)-based molecular techniques have been useful for the genetic characterization of T. gondii. Serotyping methods based on polymorphic polypeptides have the potential to become the choice for typing T. gondii in humans and animals. In this review, we summarize conventional non-DNA-based diagnostic methods, and the DNA-based molecular techniques for the diagnosis and genetic characterization of T. gondii. These techniques have provided foundations for further development of more effective and accurate detection of T. gondii infection. These advances will contribute to an improved understanding of the epidemiology, prevention and control of toxoplasmosis.

Molecular detection of Toxoplasma gondii in snakes.

Science.gov (United States)

Nasiri, Vahid; Teymurzadeh, Shohreh; Karimi, Gholamreza; Nasiri, Mehdi

2016-10-01

Toxoplasma gondii, an obligate intracellular protozoan parasite, is responsible for one of the most common zoonotic parasitic diseases in almost all warm-blooded vertebrates worldwide, and it is estimated that about one-third of the world human population is chronically infected with this parasite. Little is known about the circulation of T. gondii in snakes and this study for the first time aimed to evaluate the infection rates of snakes by this parasite by PCR methods. The brain of 68 Snakes, that were collected between May 2012 and September 2015 and died after the hold in captivity, under which they were kept for taking poisons, were examined for the presence of this parasite. DNA was extracted and Nested-PCR method was carried out with two of pairs of primers to detect the 344 bp fragment of T. gondii GRA6 gene. Five positive nested-PCR products were directly sequenced in the forward and reverse directions by Sequetech Company (Mountain View, CA). T. gondii GRA6 gene were detected from 55 (80.88%) of 68 snakes brains. Sequencing of the GRA6 gene revealed 98-100% of similarity with T. gondii sequences deposited in GenBank. To our knowledge, this is the first study of molecular detection of T. gondii in snakes and our findings show a higher frequency of this organism among them. Copyright © 2016 Elsevier Inc. All rights reserved.

Crioconservación de toxoplasma gondii

Directory of Open Access Journals (Sweden)

Sofía Duque Beltrán

1992-03-01

Full Text Available Toxoplasma gondii fue crioconservado en nitrógeno líquido usando como preservativo glicerol al 10% con el fin de mantener el protozoo por un largo período de tiempo. El descongelamiento de T. gondii se llevó a cabo, cuando los parásitos fueron requeridos para uso como antígeno, a los 10, 40 y 270 días siguientes a su crioconservación. La viabilidad y patogenicidad del parásito fue confirmada in vivo. La crioconservación de T. gondii disminuyó los costos de mantenimiento in vivo y de recursos humanos tanto en el bioterio como en el laboratorio.

Evaluation of homologous, heterologous, and affinity conjugates for the serodiagnosis of Toxoplasma gondii and Neospora caninum in maned wolves (Chrysocyon brachyurus).

Science.gov (United States)

Silva, D A O; Vitaliano, S N; Mineo, T W P; Ferreira, R A; Bevilacqua, E; Mineo, J R

2005-10-01

Use of serological tests in the diagnosis of infectious diseases in wild animals has several limitations, primarily the difficulty of obtaining species-specific reagents. Wild canids, such as maned wolves (Chrysocyon brachyurus), are highly predisposed to infection by Toxoplasma gondii and, to a lesser extent, to Neospora caninum. The aim of the present study was to evaluate homologous, heterologous, and affinity conjugates in enzyme-linked immunosorbent assays (ELISAs) and indirect fluorescent antibody tests (IFATs) for detecting immunoglobulin (Ig) G antibodies against T. gondii and N. caninum in maned wolves. Serum samples were obtained from 59 captive animals in Brazil and tested by ELISA for T. gondii serology and IFAT for N. caninum serology using 3 different enzymatic and fluorescent conjugates: homologous (guinea pig anti-maned wolf IgG-peroxidase and -fluorescein isothiocyanate [FITC]), heterologous (rabbit anti-dog IgG-peroxidase and -FITC), and affinity (protein A-peroxidase and -FITC). Seropositivity to T. gondii was comparable among the homologous (69.5%), heterologous (74.6%), and affinity (71.2%) enzymatic conjugates. A significant positive correlation was found between the antibody levels determined by the 3 enzymatic conjugates. The highest mean antibody levels (ELISA index = 4.5) were observed with the protein A-peroxidase conjugate. The same seropositivity to N. caninum (8.5%) was found with the homologous and heterologous fluorescent conjugates, but protein A-FITC was not able to detect or confirm any positive samples with homologous or heterologous conjugates. Our results demonstrate that homologous, heterologous, and affinity conjugates might be used in ELISA for serological assays of T. gondii in wild canids, whereas for N. caninum infection, only the homologous or heterologous fluorescent conjugates have been shown to be useful.

Toxoplasma gondii infection in humans in China

Directory of Open Access Journals (Sweden)

He Shenyi

2011-08-01

Full Text Available Abstract Toxoplasmosis is a zoonotic infection of humans and animals, caused by the opportunistic protozoan Toxoplasma gondii, a parasite belonging to the phylum Apicomplexa. Infection in pregnant women may lead to abortion, stillbirth or other serious consequences in newborns. Infection in immunocompromised patients can be fatal if not treated. On average, one third of people are chronically infected worldwide. Although very limited information from China has been published in the English journals, T. gondii infection is actually a significant human health problem in China. In the present article, we reviewed the clinical features, transmission, prevalence of T. gondii infection in humans in China, and summarized genetic characterizations of reported T. gondii isolates. Educating the public about the risks associated with unhealthy food and life style habits, tracking serological examinations to special populations, and measures to strengthen food and occupational safety are discussed.

Sarcocystis neurona merozoites express a family of immunogenic surface antigens that are orthologues of the Toxoplasma gondii surface antigens (SAGs) and SAG-related sequences.

Science.gov (United States)

Howe, Daniel K; Gaji, Rajshekhar Y; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-02-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s).

Sarcocystis neurona Merozoites Express a Family of Immunogenic Surface Antigens That Are Orthologues of the Toxoplasma gondii Surface Antigens (SAGs) and SAG-Related Sequences†

Science.gov (United States)

Howe, Daniel K.; Gaji, Rajshekhar Y.; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-01-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s). PMID:15664946

Genetic diversity of Toxoplama gondii isolates from Ethiopian feral cats

Science.gov (United States)

Recent studies indicate greater genetic variability among isolates of Toxoplasma gondii worldwide than previously thought. However, there is no information on genetic diversity of T. gondii from any host in Ethiopia. In the present study, genotyping was performed on viable T. gondii isolates by bioa...

Fatal Toxoplasma gondii infection in the giant panda

Directory of Open Access Journals (Sweden)

2015-01-01

Full Text Available Toxoplasma gondii can infect nearly all warm-blooded animals. We report an acute fatal T. gondii infection in the endangered giant panda (Ailuropoda melanoleuca in a zoo in China, characterized by acute gastroenteritis and respiratory symptoms. T. gondii infection was confirmed by immunological and molecular methods. Multilocus nested PCR-RFLP revealed clonal type I at the SAG1 and c29-2 loci, clonal type II at the SAG2, BTUB, GRA6, c22-8, and L358 loci, and clonal type III at the alternative SAG2 and SAG3 loci, thus, a potential new genotype of T. gondii in the giant panda. Other possible pathogens were not detected. To our knowledge, this is the first report of clinical toxoplasmosis in a giant panda.

ARF6, PI3-kinase and host cell actin cytoskeleton in Toxoplasma gondii cell invasion

International Nuclear Information System (INIS)

Vieira da Silva, Claudio; Alves da Silva, Erika; Costa Cruz, Mario; Chavrier, Philippe; Arruda Mortara, Renato

2009-01-01

Toxoplasma gondii infects a variety of different cell types in a range of different hosts. Host cell invasion by T. gondii occurs by active penetration of the host cell, a process previously described as independent of host actin polymerization. Also, the parasitophorous vacuole has been shown to resist fusion with endocytic and exocytic pathways of the host cell. ADP-ribosylation factor-6 (ARF6) belongs to the ARF family of small GTP-binding proteins. ARF6 regulates membrane trafficking and actin cytoskeleton rearrangements at the plasma membrane. Here, we have observed that ARF6 is recruited to the parasitophorous vacuole of tachyzoites of T. gondii RH strain and it also plays an important role in the parasite cell invasion with activation of PI3-kinase and recruitment of PIP 2 and PIP 3 to the parasitophorous vacuole of invading parasites. Moreover, it was verified that maintenance of host cell actin cytoskeleton integrity is important to parasite invasion.

Isolation and Genotyping of Toxoplasma gondii in Brazilian Dogs.

Science.gov (United States)

da Silva, Jamille Rodrigues; Maciel, Bianca Mendes; de Santana Souza Santos, Luana Karla Nogueira; Carvalho, Fábio Santos; de Santana Rocha, Daniele; Lopes, Carlos Wilson Gomes; Albuquerque, George Rêgo

2017-06-01

Strains of Toxoplasma gondii in Brazil are highly genetically diverse compared to strains from North America and Europe. Dogs are epidemiologically important because they act as sentinels for T. gondii infections in humans and are good indicators of environmental contamination. The aim of this study was to isolate and genetically characterize T. gondii strains from tissues of naturally infected Brazilian dogs. For this study, 21 blood samples were collected from dogs at the Zoonosis Control Centers of Ilhéus and Itabuna cities, Bahia, Brazil. The sera were examined for T. gondii antibodies using the indirect hemagglutination test. Brains and hearts of seropositive dogs were bioassayed in mice to isolate and characterize T. gondii parasites by PCR-RFLP using 10 genetic markers (SAG1, newSAG2, SAG3, BTUB, c22-8, c29-2, GRA6, PK1, APICO, and L358). However, T. gondii was isolated from only 4 (57.1%) dogs, designated TgDgBr6, 13, 17, and 21. All strains were virulent, causing clinical changes (rough hair coat, lethargy, and abdominal distention) and the death of all mice within 8-20 days after inoculation. Genetic analysis of these 4 T. gondii isolates revealed 4 distinct genotypes with different clonal lineage combinations (types I, II, and III) and 2 atypical alleles. Using PCR-RFLP with several markers, this study contributes to evaluations of the genetic diversity of strains circulating in Brazil.

Sexual transmission of Toxoplasma gondii in sheep.

Science.gov (United States)

Lopes, Welber Daniel Zanetti; Rodriguez, Joana D'Ark; Souza, Fernando A; dos Santos, Thais Rabelo; dos Santos, Ricardo Silva; Rosanese, Walter Matheus; Lopes, Werik Renato Zanetti; Sakamoto, Cláudio Alessandro; da Costa, Alvimar José

2013-07-01

Male sheep of reproductive age were distributed into three groups: GI, a sheep inoculated (oral) with 2.0×10(5) oocysts of the P strain of Toxoplasma gondii; GII, a sheep infected (subcutaneous) with 1.0×10(6) tachyzoites of the RH strain of T. gondii; and GIII, a sheep kept as a control (not infected). After the inoculation of the males, 12 breeding ewes, which were not pregnant and which were serologically negative for reproductive diseases (particularly toxoplasmosis), were distributed into three groups, synchronized, and subsequently exposed to natural mating with previously inoculated males. The distribution was as follows: five ewes that underwent natural mating with the GI male, five ewes that were exposed to natural mating with the GII male, and two ewes that were mated with the non-infected male (control). Serum samples of all the ewes were collected on days -30, -14, -7, -1, and 0 (days before natural mating) and on days 1, 3, 5, 7, 11, 14, and weekly until birth; the presence of serum antibodies against T. gondii was assessed by IFAT. Using a bioassay and PCR, T. gondii was isolated from the semen of the infected reproducing sheep before mating. Following natural mating, 5 of the 12 females displayed antibodies specific for T. gondii; of these animals, two of the ewes underwent natural mating with the male inoculated with oocysts (GI) and three with the male infected with tachyzoites (GII). One of the females that displayed antibodies specific to this coccidian and that underwent natural mating with the GII sheep had a macerated fetus on the 70th day following coverage. Using a bioassay after the birth, it was possible to isolate T. gondii from samples of the "pool" of tissues from the five females that seroconverted after natural mating and from their respective lambs. Using PCR, the DNA of T. gondii was isolated from the "pool" of tissues from one and two females exposed to natural mating with the reproductive males infected with the oocysts and

Seroprevalence of Toxoplasma gondii infection amongst residents ...

African Journals Online (AJOL)

Toxoplasmosis is a zoonotic disease, recognized as a serious public health problem worldwide. Toxoplasma gondii infection has become a major public health concern in recent years due to the ravaging HIV/AIDS pandemic. A serological survey was carried out in Tanga district of north-eastern Tanzania to assess T. gondii ...

Toxoplasma gondii coinfection with diseases and parasites in wild rabbits in Scotland.

Science.gov (United States)

Mason, Sam; Dubey, J P; Smith, Judith E; Boag, Brian

2015-09-01

In wild rabbits (Oryctolagus cuniculus) on an estate in Perthshire, central Scotland, the seroprevalence of Toxoplasma gondii was 18/548 (3·3%). The wild rabbit could be a T. gondii reservoir and it has potential value as a sentinel of T. gondii in environmental substrates. Toxoplasma gondii was associated with female sex (P myxomatosis caused by the virus Myxomatosis cuniculi, the intensity of roundworm eggs, the year or season, rabbit age or distance from farm buildings. Coinfections could have been affected by gestational down regulation of type 1 T helper cells. A sudden influx or release of T. gondii oocysts might have occurred. This is the first report of T. gondii in any wild herbivore in Scotland and also the first report of lapine T. gondii as a coinfection with E. stiedae, M. cuniculi and helminths.

Adenosine metabolism in Toxoplasma gondii: potential targets for chemotherapy.

Science.gov (United States)

el Kouni, Mahmoud H

2007-01-01

Toxoplasma gondii is an intracellular parasitic protozoan that infects approximately a billion people worldwide. Infection with T. gondii represents a major health problem for immunocompromised individuals, such as AIDS patients, organ transplant recipients, and the unborn children of infected mothers. Currently available drugs usually do not eradicate infection and as many as 50% of the patients do not respond to this therapy. Furthermore, they are ineffective against T. gondii tissue cysts. In addition, prolonged exposure to these drugs induces serious host toxicity forcing the discontinuation of the therapy. Finally, there is no effective vaccine currently available for the treatment of toxoplasmosis. Therefore, it is necessary to develop new and effective drugs for the treatment and management of toxoplasmosis. The rational design of a drug depends on the exploitation of fundamental biochemical or physiological differences between pathogens and their host. Some of the most striking differences between T. gondii and their mammalian host are found in purine metabolism. T. gondii, like most parasites studied, lack the ability to synthesize purines do novo and depend on the salvage of purines from their host to satisfy their requirements of purines. In this respect, the salvage of adenosine is the major source of purines in T. gondii. Therefore, interference with adenosine uptake and metabolism in T. gondii can be selectively detrimental to the parasite. The host cells, on the other hand, can still obtain their purine requirements by their de novo pathways. This review will focus on the broad aspects of the adenosine transport and the enzyme adenosine kinase (EC 2.7.1.20) which are the two primary routes for adenosine utilization in T. gondii, in an attempt to illustrate their potentials as targets for chemotherapy against this parasite.

Pulmonary exposure to single-walled carbon nanotubes does not affect the early immune response against Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Swedin Linda

2012-05-01

Full Text Available Abstract Background Single-walled carbon nanotubes (SWCNT trigger pronounced inflammation and fibrosis in the lungs of mice following administration via pharyngeal aspiration or inhalation. Human exposure to SWCNT in an occupational setting may occur in conjunction with infections and this could yield enhanced or suppressed responses to the offending agent. Here, we studied whether the sequential exposure to SWCNT via pharyngeal aspiration and infection of mice with the ubiquitous intracellular parasite Toxoplasma gondii would impact on the immune response of the host against the parasite. Methods C57BL/6 mice were pre-exposed by pharyngeal administration of SWCNT (80 + 80 μg/mouse for two consecutive days followed by intravenous injection with either 1x103 or 1x104 green fluorescence protein and luciferase-expressing T. gondii tachyzoites. The dissemination of T. gondii was monitored by in vivo bioluminescence imaging in real time for 7 days and by plaque formation. The inflammatory response was analysed in bronchoalveolar lavage (BAL fluid, and by assessment of morphological changes and immune responses in lung and spleen. Results There were no differences in parasite distribution between mice only inoculated with T. gondii or those mice pre-exposed for 2 days to SWCNT before parasite inoculum. Lung and spleen histology and inflammation markers in BAL fluid reflected the effects of SWCNT exposure and T. gondii injection, respectively. We also noted that CD11c positive dendritic cells but not F4/80 positive macrophages retained SWCNT in the lungs 9 days after pharyngeal aspiration. However, co-localization of T. gondii with CD11c or F4/80 positive cells could not be observed in lungs or spleen. Pre-exposure to SWCNT did not affect the splenocyte response to T. gondii. Conclusions Taken together, our data indicate that pre-exposure to SWCNT does not enhance or suppress the early immune response to T. gondii in mice.

Fatal Toxoplasma gondii infection in the giant panda.

Science.gov (United States)

Ma, Hongyu; Wang, Zedong; Wang, Chengdong; Li, Caiwu; Wei, Feng; Liu, Quan

2015-01-01

Toxoplasma gondii can infect nearly all warm-blooded animals. We report an acute fatal T. gondii infection in the endangered giant panda (Ailuropoda melanoleuca) in a zoo in China, characterized by acute gastroenteritis and respiratory symptoms. T. gondii infection was confirmed by immunological and molecular methods. Multilocus nested PCR-RFLP revealed clonal type I at the SAG1 and c29-2 loci, clonal type II at the SAG2, BTUB, GRA6, c22-8, and L358 loci, and clonal type III at the alternative SAG2 and SAG3 loci, thus, a potential new genotype of T. gondii in the giant panda. Other possible pathogens were not detected. To our knowledge, this is the first report of clinical toxoplasmosis in a giant panda. © H. Ma et al., published by EDP Sciences, 2015.

Toxoplasma gondii in wild and domestic animals from New Caledonia

Directory of Open Access Journals (Sweden)

Roqueplo C.

2011-11-01

Full Text Available Samples (serum or meat juice collected from 205 animals in New Caledonia in April 2009 were tested for antibodies against Toxoplasma gondii by ELISA using the multi-species ID Screen® Toxoplasmosis Indirect kit (IDVET, Montpellier. Antibodies to T. gondii were detected in 2% (1/49 of the pigs, in 3.3% (1/30 of the cattle, in 13.8% (4/29 of Rusa deers, in 16% (4/25 of the horses, in 32.8% (21/64 of the dogs, and in 50% (4/8 of cats. Statistically, no significant difference was observed between T. gondii seroprevalence and age or sex. No survey on the prevalence of T. gondii in animals has ever been conducted in New Caledonia and this is the first serological evidence of T. gondii in Rusa deer (Cervus timorensis russa. These results indicate an important circulation of T. gondii exists in the animal populations of New Caledonia. In view of humans being exposed, it is advisable to insist on sanitary education and on respect for good hygienic and food practice.

The Evolution of Host Mitochondrial Association and its Impact on Toxoplasma gondii Infection

Science.gov (United States)

English, Elizabeth D.

The association of intracellular pathogens with host mitochondria has been observed across taxa, from bacterial pathogens, such as Legionella pneumophila and Chlamydia trachomati, to the eukaryotic pathogen Toxoplasma gondii. However the functional impact of host mitochondrial association (HMA) remains difficult to assess in most of these species because in many cases the genes responsible for this phenomenon have not yet been identified. The recent discovery of the T. gondii gene responsible for HMA, Mitochondrial Association Factor 1 ( MAF1) has provided us with the tools to begin to understand the evolution and impact of HMA. Here we use multispecies sequence analysis to determine that the MAF1 locus is tandemly duplicated and diversified in both T. gondii and its nearest extant relative Hammondia hammondi, but not another close relative Neospora caninum. Using cross-species complementation we find that T. gondii and H. hammondi harbor copies of MAF1 able to mediate HMA, while N. caninum does not. We have begun mutational analysis using naturally occurring HMA+ and HMA- paralogs of MAF1 in order to determine the portions of MAF1 protein necessary for HMA. Additionally, we have identified the first in vivo phenotypes associated with HMA using multiple mouse models, for both acute and chronic infection. Taken together these data indicate that HMA likely evolved via neofunctionalization of a duplicated ancestral MAF1 gene, and that the neofunctionalized, HMA competent copy of MAF1 provides a selective advantage.

Toxoplasma gondii gamma irradiation using Co-60

International Nuclear Information System (INIS)

Serra-Freire, Nicolau Maues

1996-01-01

The use of nuclear power through radiation for the destruction of microorganisms which cause food deterioration, infections and toxicosis, is specifically for peaceful purposes. Toxoplasma gondii is a protozoa responsible for illnesses in humans and animals. One of the most common ways of transmission is through raw or poorly cooked meat. There is little information on the resistance of T. gondii to radiation. The objective of this research is to determine the Minimum Lethal Dose (MLD) of gamma radiation for those microorganisms. Suspensions of T. gondii containing approximately one million taquizoites/ml were irradiated with doses between up 0,01 up to 0,15 kGy (Kilogray) and inoculated to mice. The surviving T. gondii were re-irradiated with 0,01 up to 0,16 kGy. The irradiated protozoa were totally destroyed with a 0,15 kGy dose (MLD). Taquizoites issued from live protozoa of 0,14 kGy also were completely destroyed with dose of 0,15 kGy. No increase in resistance was observed regarding the non irradiated protozoa. (author)

First report of Toxoplasma gondii seroprevalence in pet parrots in China.

Science.gov (United States)

Zhang, Xiao-Xuan; Zhang, Nian-Zhang; Tian, Wei-Peng; Zhou, Dong-Hui; Xu, Ying-Tian; Zhu, Xing-Quan

2014-06-01

Toxoplasmosis, caused by the obligate intracellular protozoan parasite Toxoplasma gondii, has become a serious public health problem worldwide. T. gondii can infect almost all warm-blooded animals, including parrots. However, little is known of T. gondii infection in parrots in China. Antibodies against T. gondii in 311 parrots including 202 Budgerigars (Melopsittacus undulatus), 26 Lovebirds (Agapornis sp.), 22 Cockatiels (Nymphicus hollandicus), and 61 Alexandrine Parakeets (Psittacula eupatria) in the cities of Beijing and Weifang in north China were tested using the modified agglutination test (MAT). Twenty-six (8.36%) out of 311 serum samples were positive for T. gondii at the cutoff of 1:5. Among the four species, a higher seroprevalence of T. gondii was found in Cockatiels (13.64%, 95% confidence interval [CI] 0.00-27.98), although the difference was not statistically significant (p=0.61). Seropositivity rates against T. gondii in male parrots (10.43%, 95% CI 5.74-15.12) were not statistically different from that in female parrots (6.08%, 95% CI 2.23-9.93, p=0.17). The seropositivity of T. gondii in parrots from Weifang and Beijing was 11.11% (95% CI 6.13-16.09) and 5.70% (95% CI 2.08-9.31), respectively. The seroprevalence varied in parrots of different age groups, ranging from 5.71% (95% CI 1.27-10.15) to 13.00% (95% CI 6.41-19.69), however, the difference among age groups was not statistically significant (p=0.12). The seroprevalence of T. gondii infection in parrots in summer (11.63%, 95% CI 6.84-16.42) was significantly higher than in spring (4.32%, 95% CI 0.94-7.70, p=0.02). The results of the present survey indicated that parrots in China are exposed to T. gondii. To our knowledge, this is the first report of T. gondii seroprevalence in parrots in China.

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 ...

Genetic diversity of Toxoplasma gondii isolates from Ethiopian feral cats.

Science.gov (United States)

Dubey, J P; Choudhary, S; Tilahun, G; Tiao, N; Gebreyes, W A; Zou, X; Su, C

2013-09-01

Recent studies indicate greater genetic variability among isolates of Toxoplasma gondii worldwide than previously thought. However, there is no information on genetic diversity of T. gondii from any host in Ethiopia. In the present study, genotyping was performed on viable T. gondii isolates by bioassays in mice from tissues and feces of 27 cats from Ethiopia. Viable T. gondii was isolated from hearts of 26 cats, feces alone of 1 cat, and feces and tissues of 6 cats; in total there were 33 isolates. Genotyping was performed on DNA from cell-cultured derived T. gondii tachyzoites and by using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Four genotypes were recognized, including ToxoDB #1 (Type II clonal, nine isolates), ToxoDB #2 (Type III, five isolates), Toxo DB #3 (Type II variant, ten isolates), and ToxoDB #20 (nine isolates). Of interest is the isolation of different genotypes from tissues and feces of two cats, suggesting re-infection or mixed strain T. gondii infection. These findings are of epidemiological significance with respect to shedding of oocysts by cats. This is the first report of genotyping of T. gondii from any host in Ethiopia. Published by Elsevier B.V.

Seropositivity of Toxoplasma gondii in domestic donkeys (Equus asinus) and isolation of T. gondii from farm cats.

Science.gov (United States)

Dubey, J P; Ness, S L; Kwok, O C H; Choudhary, S; Mittel, L D; Divers, T J

2014-01-17

Donkeys (Equus asinus) are used as both companion and working animals throughout the world and in some countries, their meat and milk are used for human consumption. Here we report the first serological survey of Toxoplasma gondii in donkeys in the United States. Serum samples from 373 donkeys from eight farms in five states were tested for T. gondii antibodies by the modified agglutination test (MAT). Twenty-four of 373 (6.4%) of donkeys were seropositive, with MAT titers ranging from 25 to ≥ 200. All seropositive donkeys were Miniature breed. Seropositivity prevalence was 7.0% in female donkeys (20/282) and 4.1% in male donkeys (4/91). No donkeys less than 24 months of age (129) were seropositive, suggesting postnatal transmission of infection. Domestic cats were present on six of the eight farms. Three cats from one farm had MAT titers of 200. Viable T. gondii was isolated from the hearts of two cats, but not from brain tissues. Genotyping of isolate DNA extracted from culture-derived tachyzoites using 10 PCR-restriction fragment length polymorphism (RFLP) markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, PK1, L358 and Apico loci) revealed that both isolates were clonal Type II (ToxoDB PCR-RFLP genotype #1). This is the first serological survey for T. gondii in donkeys in the United States, and suggests that donkey milk and meat should be considered as a potential source for human infection. The role of barn cats in the transmission of T. gondii to donkeys on farms warrents further investigation. Copyright © 2013 Elsevier B.V. All rights reserved.

Prevalence of Toxoplasma gondii in Canadian market-age pigs.

Science.gov (United States)

Gajadhar, A A; Aramini, J J; Tiffin, G; Bisaillon, J R

1998-08-01

During 1991 and 1992, 2,800 market-age pigs were sampled at federally inspected abattoirs from across Canada. Anti-Toxoplasma gondii IgG at titers of > or =1:32 were found in 240 pigs examined by a commercial, latex agglutination test. Seroprevalences ranged from 3.5 to 13.2% in the different regions of the country. Tissue hybridization studies using a previously developed probe demonstrated T. gondii ribosomal RNA in 9 of 36 animals, whereas mouse bioassay testing of heart muscle and diaphragm from all 2,800 pigs failed to demonstrate the presence of infective stages of T. gondii in tissues. Although serology results from this study indicated that Canadian market-age pigs are infected with T. gondii at rates similar to those reported from other parts of North America, mouse bioassay results suggested that Canadian pork products contain low levels of infective organisms. This apparent discrepancy suggests that serological evidence of T. gondii infection in pigs alone does not accurately assess the public health risks associated with consuming improperly cooked pork products.

Seroprevalence of Toxoplasma gondii infection in slaughtered pigs ...

African Journals Online (AJOL)

Toxoplasmosis is a parasitic disease/infection of medical and veterinary importance. The causative agent; Toxoplasma gondii, can infect warm blooded animals, birds as well as humans. This study was designed to determine the seroprevalence of Toxoplasma gondii infection in slaughtered pigs in Makurdi, Nigeria.

Targeted Delivery of Toxoplasma gondii Antigens to Dendritic Cells Promote Immunogenicity and Protective Efficiency against Toxoplasmosis

Directory of Open Access Journals (Sweden)

Zineb Lakhrif

2018-02-01

Full Text Available Toxoplasmosis is a major public health problem and the development of a human vaccine is of high priority. Efficient vaccination against Toxoplasma gondii requires both a mucosal and systemic Th1 immune response. Moreover, dendritic cells play a critical role in orchestrating the innate immune functions and driving specific adaptive immunity to T. gondii. In this study, we explore an original vaccination strategy that combines administration via mucosal and systemic routes of fusion proteins able to target the major T. gondii surface antigen SAG1 to DCs using an antibody fragment single-chain fragment variable (scFv directed against DEC205 endocytic receptor. Our results show that SAG1 targeting to DCs by scFv via intranasal and subcutaneous administration improved protection against chronic T. gondii infection. A marked reduction in brain parasite burden is observed when compared with the intranasal or the subcutaneous route alone. DC targeting improved both local and systemic humoral and cellular immune responses and potentiated more specifically the Th1 response profile by more efficient production of IFN-γ, interleukin-2, IgG2a, and nasal IgA. This study provides evidence of the potential of DC targeting for the development of new vaccines against a range of Apicomplexa parasites.

Proteomic characterization of the subpellicular cytoskeleton of Toxoplasma gondii tachyzoites.

Science.gov (United States)

Gómez de León, Carmen T; Díaz Martín, Rubén Darío; Mendoza Hernández, Guillermo; González Pozos, Sirenia; Ambrosio, Javier R; Mondragón Flores, Ricardo

2014-12-05

Toxoplasma, the causative agent of toxoplasmosis in animals and humans, has a subpellicular cytoskeleton that is involved in motility, cell shape and invasion. Knowledge of components of the cytoskeleton is necessary to understand the invasion mechanisms as well as for the identification of possible therapeutic targets. To date, most cytoskeletal components of Toxoplasma remain unidentified due mainly to the lack of reproducible methods for their isolation. Based on the successful isolation of the cytoskeleton, it was possible to report for the first time, the proteomic characterization of the subpellicular cytoskeleton of Toxoplasma formed by 95 cytoskeletal proteins through proteomic analysis by tandem mass spectrometry of one dimension SDS PAGE. By bioinformatic analysis of the data, proteins were classified as: 18 conventional cytoskeletal proteins; 10 inner membrane complex proteins, including 7 with alveolin repeats; 5 new proteins with alveolin like repeats; 37 proteins associated with other organelles and 25 novel proteins of unknown function. One of the alveolin like proteins not previously described in Toxoplasma named TgArticulin was partially characterized with a specific monoclonal antibody. Presence of TgArticulin was exclusively associated with the cytoskeleton fraction with a cortical distribution. Functions for the several molecules identified are proposed. This manuscript describes, for the first time, the proteome of the subpellicular cytoskeleton of Toxoplasma gondii. The importance of this study is related to the role of the cytoskeleton in the highly invasive capability of a parasite that causes abortion, blindness, and death by encephalitis in immunocompromised patients. Proteomic characterization of the cytoskeleton of T. gondii tachyzoites was possible by the development of a successful procedure for the isolation of the subpellicular cytoskeleton. Knowledge of the composition of the cytoskeleton of Toxoplasma is fundamental for the

High prevalence of Toxoplasma gondii antibodies in dogs in Veracruz, Mexico

Science.gov (United States)

Little is known concerning the prevalence of Toxoplasma gondii infection in dogs in Mexico. Here, we investigated antibodies to T. gondii and associated risk factors in 101 dogs from an animal shelter in Veracruz State, Mexico. Canine sera were assayed for T. gondii IgG antibodies by using the modif...

Evaluating Recombinant Antigen ROP1 Efficacy in Diagnosis of Toxoplasma Gondii Infection

Directory of Open Access Journals (Sweden)

F Keshavarzi

2015-07-01

Full Text Available Introduction:Toxoplasma gondii is a ubiquitous obligate intracellular parasite with a relatively broad host range infecting both mammals and birds. Toxoplasma proteins are strong antigens that can begin strong immune reactions, among which Rhoptry protein 1 (ROP1 can be named discharging from rhoptry cell-organ. ROP1 is regarded as a competitor for recombinant vaccines against toxoplasmosis. Therefore, the main objective of the current study was to evaluate the cloning and expression of ROP1 Toxoplasma gondii in a cloning vector as well as to create this recombinant antigen in order to be applied for later uses. Methods:Genomic DNA of Toxoplasma gondii was removed and reproduced by PCR, then the PCR product was cloned into the EcoR1 and BamH1 sites of cloning vector, pUET1, and transformed into Escherichia coli BL21 plysS strain. Moreover, pcROP1 was sub-cloned into the HindIII and EcoRI sites of the pcDNA3 in order to produce recombining eukaryotic declaration vector. The cloned ROP1 was verified by PCR, limitation enzymes (HindIII and BglΙ digestion and nucleotide sequencing. Then, this recombinant antigen was covered applying IgM and ELISAIgG. Results:The study results demonstrated that a fragment of 757 bp was separated. In addition, nucleotide sequence analysis of the ROP1 cloned in pUET1vector revealed high homology (96% with RH strain Gene Bank Accession (No. M71274. Conclusion:The recombinant ROP1 antigen in an IgM Rec-ELISA test can be replaced with the tachyzoite antigen in IgG and IgM serologic tests.

Toxoplasma gondii seroprevalence in dairy and beef cattle

DEFF Research Database (Denmark)

Jokelainen, Pikka; Tagel, Maarja; Motus, Kerli

2017-01-01

Toxoplasma gondii is a zoonotic protozoan parasite that thrives in Estonia. In this nationwide cross-sectional study, we tested sera from 3991 cattle, collected from 228 farms in 2012–2013, for anti-T. gondii immunoglobulin G antibodies using a commercial direct agglutination test. Titer of 100 w...

Seroprevalence of Toxoplasma gondii infection in goats from the south-west region of Poland and the detection of T. gondii DNA in goat milk.

Science.gov (United States)

Sroka, Jacek; Kusyk, Pawel; Bilska-Zajac, Ewa; Karamon, Jacek; Dutkiewicz, Jacek; Wojcik-Fatla, Angelina; Zajac, Violetta; Stojecki, Krzysztof; Rozycki, Miroslaw; Cencek, Tomasz

2017-07-11

Toxoplasma gondii (Nicolle et Manceaux, 1908) is an obligatory intracellular protozoan parasite prevalent in animals and humans worldwide having medical and veterinary importance on account of causing abortion or congenital disease in intermediate hosts, including man. Since T. gondii has already been identified in the milk of goats, Capra aegagrus hircus (Linnaeus), the possibility of acquiring infection by ingesting unpasteurised goat milk should be taken into consideration. Thus, the aim of the present study was to determine the presence of T. gondii DNA in goat milk. First, 73 goats (females) from 36 farms located in Poland were examined serologically by direct agglutination test (DAT) to estimate the T. gondii serological status. Milk samples from 60 selected lactating females were examined for the presence of T. gondii DNA by Real time PCR and nested PCR (B1 gene). To estimate the clonal type of detected T. gondii, multiplex PCR was performed using 6 markers. In DAT, positive results were found in 70% of 73 goats. Among examined 60 milk samples, 65% were positive in Real time PCR and 43% in nested PCR. It is noteworthy that 11 samples positive in PCR were collected from seronegative goats. The multilocus PCR analysis mostly revealed the occurrence of genotype III, which is relatively rare in Europe. The recorded high prevalence of anti-Toxoplasma antibodies in tested goats (70%), associated with a high prevalence of T. gondii DNA in goat milk samples (65%), indicates a potential risk of the parasite transmission through goat milk ingestion.

Toxoplasma gondii sequesters lysosomes from mammalian hosts in the vacuolar space.

Science.gov (United States)

Coppens, Isabelle; Dunn, Joe Dan; Romano, Julia D; Pypaert, Marc; Zhang, Hui; Boothroyd, John C; Joiner, Keith A

2006-04-21

The intracellular compartment harboring Toxoplasma gondii satisfies the parasite's nutritional needs for rapid growth in mammalian cells. We demonstrate that the parasitophorous vacuole (PV) of T. gondii accumulates material coming from the host mammalian cell via the exploitation of the host endo-lysosomal system. The parasite actively recruits host microtubules, resulting in selective attraction of endo-lysosomes to the PV. Microtubule-based invaginations of the PV membrane serve as conduits for the delivery of host endo-lysosomes within the PV. These tubular conduits are decorated by a parasite coat, including the tubulogenic protein GRA7, which acts like a garrote that sequesters host endocytic organelles in the vacuolar space. These data define an unanticipated process allowing the parasite intimate and concentrated access to a diverse range of low molecular weight components produced by the endo-lysosomal system. More generally, they identify a unique mechanism for unidirectional transport and sequestration of host organelles.

Meat juice serology for Toxoplasma gondii infection in chickens

Directory of Open Access Journals (Sweden)

Alice Vismarra

2016-01-01

Full Text Available Toxoplasma gondii is an important foodborne zoonosis. Free-range chickens are at particularly high risk of infection and are also excellent indicators of soil contamination by oocysts. In the present study, hearts of 77 freerange chickens were collected at slaughter. T. gondii meat juice enzyme-linked immunosorbent assay was performed with a commercial kit, following validation with positive controls, from experimentally infected chickens, and negative ones. Out of 77 samples, only 66 gave sufficient meat juice for serology. Of these, 24 (36.4% were positive for T. gondii considering the 5*standard deviation values (calculated on the optical density of negative controls, while all the samples were negative considering sample/positive% values. Parasite-specific polymerase chain reaction was carried out on all samples obtained from heart tissue and none were positive for the presence of T. gondii DNA. Results would suggest that further study on the use of meat juice with a validated serological test to detect T. gondii in chickens could lead to widespread epidemiological studies in this important intermediate host. However, sample collection and test specificity require further evaluation.

Experimental toxoplasma gondii infection in grey seals (Halichoerus grypus)

DEFF Research Database (Denmark)

Gajadhar, A. A.; Measures, L.; Forbes, L. B.

2004-01-01

Laboratory-reared animals were used to assess the susceptibility of seals (Halichoerus grypus) to Toxoplasma gondii infection. Four seals were each orally inoculated with 100 or 10,000 oocysts of T. gondii (VEG strain), and another 4 seals served as negative controls. Occasionally, mild behavioral...... changes were observed in all inoculated seals but not in control animals. A modified agglutination test revealed the presence of antibodies to T. gondii in sera collected from inoculated seals and mice inoculated as controls. No evidence of the parasite was found on an extensive histological examination...... of seal tissues, and immunohistochemical staining of tissue sections from inoculated seals revealed a single tissue cyst in only 1 seal. Control mice inoculated with 10 oocysts from the same inoculum given to seals became serologically and histologically positive for T. gondii. Cats that were fed brain...

Toxoplasma gondii infection and chronic schizophrenia: is there any association?

Directory of Open Access Journals (Sweden)

Salvina Maria de Campos-Carli

Full Text Available ABSTRACT Background: Toxoplasma gondii (T. gondii infection has been identified as a risk factor for schizophrenia. Objectives: Herein, we sought to evaluate the association between T. gondii infection and clinical symptoms and quality of life in patients with schizophrenia. Methods: We conducted a cross-sectional study with 48 patients with chronic schizophrenia and 40 controls. Peripheral blood was drawn, and IgM and IgG anti-T. gondii antibodies were evaluated by Enzyme-Linked Immunosorbent Assay (ELISA. Depressive, positive and negative symptoms were assessed, respectively, by the Calgary Depression Scale (CDS and the Positive and Negative Syndrome Scale (PANSS. Cognitive performance was assessed in patients by the Brazilian version of the Schizophrenia Cognition Rating Scale (SCoRS-BR. Quality of life was assessed by the Brazilian version of the Quality of Life in Schizophrenia scale (QLS-BR. Results: The prevalence and titers of T. gondii IgM and IgG antibodies did not differ between patients and controls. The positive serology for T. gondii IgG antibodies was not associated with illness symptoms, cognitive performance, depressive symptoms or quality of life. Discussion: Our findings suggest that toxoplasmosis infection is not associated with severity of symptoms, quality of life, cognitive or depressive symptoms in schizophrenia patients.

Diagnosis and isolation of Toxoplasma gondii in horses from Brazilian slaughterhouses Diagnóstico e isolamento de Toxoplasma gondii em equídeos de frigoríficos brasileiros

Directory of Open Access Journals (Sweden)

Fernanda Evers

Full Text Available This study aimed to investigate anti-Toxoplasma gondii antibodies and to isolate the parasite from the brains of horses processed at slaughterhouses in Brazil. We collected brain and blood samples from 398 horses of various ages, from six Brazilian states. Serum samples were evaluated by indirect fluorescent antibody test (IFAT cut-off titre ≥ 1:64, and brains were submitted to mouse bioassay. Among the 398 horses, positivity for T. gondii was identified in 46 (11.6% by IFAT and in 14 (3.5% by mouse bioassay. In 12 of those 14 bioassays, mice were positive only by IFAT (cut-off titre ≥ 1:16, T. gondii being isolated in the remaining two. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis of 18S rDNA to differentiate among T. gondii, Neospora caninum, and Sarcocystis neurona, we found that two of the 14 brains were positive for T. gondii only. For genotyping of the two isolates and the PCR-positive brain, we performed PCR-RFLP based on 13 markers, and SAG2 all samples were Toxoplasma gondii type I. Collectively, IFAT of horse sera and mouse bioassay identified positivity in 60 (15% of the samples. Our results show that some horses sent to slaughter in Brazil have been exposed to T. gondii.O objetivo do estudo foi investigar anticorpos anti-Toxoplasma gondii e isolar o parasita do cérebro de equídeos abatidos em matadouros-frigoríficos no Brasil. Colheram-se amostras de 398 cérebros e sangue de equídeos machos e fêmeas de idades variadas, provenientes de seis estados brasileiros. As amostras de soro foram avaliadas pelo teste de imunofluorescência indireta (IFI para T. gondii (ponto de corte ≥ 64, e os fragmentos de cérebros foram submetidos ao bioensaio em camundongos. Por meio da IFI, 46 (11,6% equídeos foram soropositivos. Pelo bioensaio em camundongos, 14 (3,5% cérebros de equídeos testados foram positivos. Em doze dos bioensaios, os camundongos foram positivos somente pela IFI (ponto

Toxoplasma gondii antibodies in the white stork Ciconia ciconia.

Science.gov (United States)

Andrzejewska, Izabela; Tryjanowski, Piotr; Zduniak, Piotr; Dolata, Pawel T; Ptaszyk, Jerzy; Cwiertnia, Piotr

2004-01-01

The prevalence of Toxoplasma gondii in chicks of wild birds and captive individuals was studied in the Poznań environs and in the Poznań Zoological Garden in the years 2002-2003. Bird blood was tested for T. gondii antibodies by an indirect fluorescent antibody test. T. gondii antibodies were detected from 5.8% of 205 analysed white stork chicks and 13.6% of 44 analysed adult storks in the zoo. Because toxoplasmosis is one of the more common parasitic zoonoses worldwide, we briefly discuss the potential epidemiological importance of stork toxoplasmosis to humans.

Prevalence and genetic characterization of Toxoplasma gondii in donkeys in northeastern China.

Science.gov (United States)

Zhang, Xiao-Xuan; Shi, Wei; Zhang, Nian-Zhang; Shi, Kun; Li, Jian-Ming; Xu, Peng; Zhao, Quan; Du, Rui

2017-10-01

Toxolasma gondii is one of the most important obligate intracellular protozoan parasites. Recently, toxoplasmosis is of increasing concerns because T. gondii not only has a worldwide distribution but also can infect virtually all warm-blooded hosts including donkeys. However, limited information is available concerning the genetic characterization of T. gondii in donkeys in northeastern China. In this study, a total of 302 brain tissue samples collected from donkeys from Jilin (n=108) and Liaoning (n=194) provinces, northeastern China, were examined for T. gondii infection by semi-nested PCR of B1 gene. The positive samples were genotyped at 11 loci (i.e., SAG1, alternative SAG2, 5'-and 3'-SAG2, SAG3, L358, BTUB, c22-8, GRA6, c29-2, PK1 and Apico) using polymerase chain reaction-restriction fragment length polymorphism technology. Of 302 brain tissue samples, 19 (6.29%) were PCR-positive for T. gondii. The prevalence rates of T. gondii were 6.48% (7/108) and 6.19% (12/194) in Jilin Province and Liaoning Province, respectively. The prevalence of T. gondii in different season groups varied from 5.56% to 7.41%. The prevalence of T. gondii in "Cage-free" donkeys was higher than that in "Captive" donkeys. Of the 19 positive samples, only two isolates were successfully genotyped at all loci, three were genotyped at 9 loci. In total, four samples belong to ToxoDB genotype #9, one belong to ToxoDB genotype #10. This is firstly characterized the T. gondii isolates from donkeys in northeastern China. The results of the present study will improve the information of the distribution of T. gondii genotypes in China. Copyright © 2017. Published by Elsevier B.V.

Seroprevalence of Toxoplasma gondii in humans and pigs in North Sulawesi, Indonesia.

Science.gov (United States)

Tuda, Josef; Adiani, Sri; Ichikawa-Seki, Madoka; Umeda, Kousuke; Nishikawa, Yoshifumi

2017-10-01

Toxoplasma gondii, an intracellular protozoan parasite, is a major public health concern throughout the world. Importantly, toxoplasmosis has several adverse effects, including neurological and ocular diseases. There are currently no data on the prevalence of T. gondii infection in humans or animals in North Sulawesi, although Indonesia is known to have a high seroprevalence of this parasite. In this study, the prevalence of T. gondii was determined in samples of humans and pigs from North Sulawesi using the latex agglutination test. In total, 856 human were sampled and 58.5% of whom were positive for T. gondii. Although the antibody prevalence in male and female children aged 0-9years was 40% in both sexes, suggesting that the transmission rate of the parasite to humans is extremely high in this area. However, the overall prevalence of T. gondii in pigs was only 2.3%. Our study indicates a high incidence of T. gondii infection in humans. Therefore, a survey of the prevalence of T. gondii among different infection sources is required to determine the major risk factors for infection in North Sulawesi. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevalence of Toxoplasma gondii infection in household and feral cats in Korea.

Science.gov (United States)

Kim, Sung-Eon; Choi, Ran; Kang, Seung-Won; Hyun, Changbaig

2017-09-01

This study was designed to investigate the prevalence rate of Toxoplasma gondii ( T. gondii ) infection in household cats in Korea. One hundred household cats and 50 feral cats from nine of the largest cities in Korea were enrolled in this study. The tests performed in this survey was an in-house rapid screen IgG and IgM combo test, faecal PCR test for T. gondii oocysts, and an ELISA immunoassay for IgG antibodies. There were no household cats positive for T. gondii infection detected using the in-house IgG and IgM rapid screen combo test, although 6/50 and 0/50 feral cats were positive in IgG and IgM tests, respectively. This initial finding was confirmed by subsequent ELISA test for IgG antibody and PCR for T. gondii in faeces. Despite the higher prevalence rate of the disease in feral cats in Korea, we did not find any household cats that were either infected or exposed previously to T. gondii in our study population. Our study indicates that there is minimal risk of T. gondii transmission from household cats to human in Korea.

First report of Toxoplasma gondii seroprevalence in peafowls in Yunnan Province, Southwestern China

Directory of Open Access Journals (Sweden)

Tian Yi-Ming

2012-09-01

Full Text Available Abstract Background Toxoplasma gondii is an intracellular protozoan parasite infecting almost all warm-blooded animals, including birds, with a worldwide distribution. Surveys of T. gondii infection in wild birds have been reported extensively in the world, but little is known of T. gondii infection in peafowls worldwide. This study was performed to determine the seroprevalence of T. gondii infection in peafowls in Yunnan Province, southwestern China. Methods Sera from 277 peafowls, including 272 blue peafowls (Pavo cristatus and 5 green peafowls (Pavo muticus originated from two geographic areas in Yunnan Province were assayed for T. gondii antibodies using the modified agglutination test (MAT. Results Specific T. gondii antibodies were detected in 35 of 277 (12.64% peafowls (MAT titer ≥ 1:5. Seropositive birds were found in both species, 33 in 272 blue peafowls and 2 in 5 green peafowls. There was no significant difference in T. gondii seroprevalence between the adolescent birds (6.74% and the adult birds (6.67% (P > 0.05. The geographical origins of peafowls was found to be highly associated with T. gondii infection in the present study, a statistically significant difference in T. gondii seropositivity was observed between peafowls from Kunming (31.08% and those from Xishuangbanna Dai Autonomous Prefecture (5.91% (OR = 10.956, 95% CI = 1.632-73.545, P = 0.014. Statistical analyses showed that there were no significant interactions between ages and geographical origins of peafowls (P > 0.05. Conclusions The results of the present survey indicated that infection of peafowls with T. gondii is widespread in Yunnan Province, which has significant public health concerns and implications for prevention and control of toxoplamosis in this province. To our knowledge, this is the first seroprevalence report of T. gondii infection in China’s southwestern Yunnan Province.

First report of Toxoplasma gondii seroprevalence in peafowls in Yunnan Province, Southwestern China.

Science.gov (United States)

Tian, Yi-Ming; Dai, Fei-Yan; Huang, Si-Yang; Deng, Zu-Hong; Duan, Gang; Zhou, Dong-Hui; Yang, Jian-Fa; Weng, Ya-Biao; Zhu, Xing-Quan; Zou, Feng-Cai

2012-09-19

Toxoplasma gondii is an intracellular protozoan parasite infecting almost all warm-blooded animals, including birds, with a worldwide distribution. Surveys of T. gondii infection in wild birds have been reported extensively in the world, but little is known of T. gondii infection in peafowls worldwide. This study was performed to determine the seroprevalence of T. gondii infection in peafowls in Yunnan Province, southwestern China. Sera from 277 peafowls, including 272 blue peafowls (Pavo cristatus) and 5 green peafowls (Pavo muticus) originated from two geographic areas in Yunnan Province were assayed for T. gondii antibodies using the modified agglutination test (MAT). Specific T. gondii antibodies were detected in 35 of 277 (12.64%) peafowls (MAT titer ≥ 1:5). Seropositive birds were found in both species, 33 in 272 blue peafowls and 2 in 5 green peafowls. There was no significant difference in T. gondii seroprevalence between the adolescent birds (6.74%) and the adult birds (6.67%) (P > 0.05). The geographical origins of peafowls was found to be highly associated with T. gondii infection in the present study, a statistically significant difference in T. gondii seropositivity was observed between peafowls from Kunming (31.08%) and those from Xishuangbanna Dai Autonomous Prefecture (5.91%) (OR = 10.956, 95% CI = 1.632-73.545, P = 0.014). Statistical analyses showed that there were no significant interactions between ages and geographical origins of peafowls (P > 0.05). The results of the present survey indicated that infection of peafowls with T. gondii is widespread in Yunnan Province, which has significant public health concerns and implications for prevention and control of toxoplamosis in this province. To our knowledge, this is the first seroprevalence report of T. gondii infection in China's southwestern Yunnan Province.

Seroepidemiology of infection with Toxoplasma gondii in healthy blood donors of Durango, Mexico

Directory of Open Access Journals (Sweden)

Estrada-Martínez Sergio

2007-07-01

Full Text Available Abstract Background Toxoplasma gondii (T. gondii infection in blood donors could represent a risk for transmission in blood recipients. There is scarce information about the epidemiology of T. gondii infection in blood donors in Mexico. Therefore, we sought to determine the prevalence of T. gondii infection and associated socio-demographic and behavioral characteristics in a population of healthy blood donors of Durango City, Mexico. Methods Four hundred and thirty two blood donors in two public blood banks of Durango City, Mexico were examined for T. gondii infection between August to September 2006. Blood donors were tested for anti-T. gondii IgG and IgM antibodies by using enzyme-linked immunoassays (Diagnostic Automation Inc., Calabasas, CA, USA. Socio-demographic and behavioral characteristics from each participant were also obtained. Results Thirty two (7.4% of 432 blood donors had IgG anti-T. gondii antibodies. Eight (1.9% of them had also IgM anti-T. gondii antibodies. Multivariate analysis using logic regression showed that T. gondii infection was associated with the presence of cats at home (adjusted OR = 3.81; 95% CI: 1.45–10.01. The age group of 45–60 years showed a significantly higher frequency of T. gondii infection than the group of 25–34 years (p = 0.02. Blood donors without education had a significantly higher frequency of infection (15.8% than those with 13–19 years of education (4.5% (p = 0.04. Other characteristics of blood donors including male gender, consumption of undercooked meat or blood transfusion did not show an association with infection. Conclusion The prevalence of T. gondii infection in healthy blood donors of Durango City, Mexico is lower than those reported in blood donors of south and central Mexico, and is one of the lowest reported in blood donors worldwide. T. gondii infection in our blood donors was most likely acquired by contact with cats. Prevalence of infection increased with age and decreased

Genotyping of polymorphic effectors of Toxoplasma gondii isolates from China

Directory of Open Access Journals (Sweden)

Weisheng Cheng

2017-11-01

Full Text Available Abstract Background Toxoplasma gondii is an opportunistic protozoan apicomplexan and obligate intracellular parasite that infects a wide range of animals and humans. Rhoptry proteins 5 (ROP5, ROP16, ROP18 and dense granules 15 (GRA15 are the important effectors secreted by T. gondii which link to the strain virulence for mice and modulate the host’s response to the parasite. Little has been known about these molecules as well as GRA3 in type Chinese 1 strains that show polymorphism among strains of archetypical genotypes. This study examined the genetic diversity of these effectors and its correlated virulence in mice among T. gondii isolates from China. Results Twenty-one isolates from stray cats were detected, of which 15 belong to Chinese 1, and 6 to ToxoDB #205. Wh6 isolate, a Chinese 1 strain, has an avirulent phenotype. PCR-RFLP results of ROP5 and ROP18 presented few variations among the strains. Genotyping of GRA15 and ROP16 revealed that all the strains belong to type II allele except Xz7 which carries type I allele. ROP16 amino acid alignment at 503 locus demonstrated that 17 isolates are featured as type I or type III (ROP16I/III, and the other 4 as type II (ROP16II. The strains investigated may be divided into four groups based on GRA3 amino acid alignment, and all isolates of type Chinese 1 belong to the μ-1 allele except Wh6 which is identical to type II strain. Conclusions PCR-RFLP and sequence alignment analyses of ROP5, ROP16, ROP18, GRA3, and GRA15 in T. gondii revealed that strains with the same genotype may have variations in some of their key genes. GRA3 variation exhibited by Wh6 strain may be associated with the difference in phenotype and pathogenesis.

Prevalence of Toxoplasma gondii infection in wild birds in Durango, Mexico.

Science.gov (United States)

Alvarado-Esquivel, C; Rajendran, C; Ferreira, L R; Kwok, O C H; Choudhary, S; Alvarado-Esquivel, D; Rodríguez-Peña, S; Villena, I; Dubey, J P

2011-10-01

There is a lack of information concerning the prevalence of Toxoplasma gondii infection in wild birds in Mexico. In the present study, serum samples and tissues from 653 birds from Durango State, Mexico, were evaluated for T. gondii infection. Antibodies to T. gondii (modified agglutination test, titer 1∶25 or higher) were found in 17 (2.6%) of the 653 birds, including 1 of 2 curve-billed thrashers (Toxostoma curvirostre), 2 (1 Anas platyrhynchos, 1 Anas diazi) of 4 ducks, 1 of 2 eagles (Aquila sp.), 5 (27.8%) of 18 great-tailed grackles (Quiscalus mexicanus), 7 (1.3%) of 521 rock pigeons (Columba livia), and 1 (14.3%) of 7 quail (Coturnix coturnix). The seroprevalence of T. gondii infection in birds captured in a park outside the city zoo (11.6%, 8/69) was significantly higher than that found in birds from other regions (1.5%, 9/584, OR  =  8.38; 95% CI: 2.82-24.77; P  =  0.0001). Brains and hearts of 23 birds (17 seropositive, 6 seronegative) were bioassayed in mice for the isolation of T. gondii . Viable T. gondii was isolated from 1 of 7 seropositive pigeons. The DNA obtained from the T. gondii isolate from the pigeon was genotyped using the PCR-RFLP typing using 11 markers (B1, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) and revealed an atypical genotype. This is the first report of T. gondii infection in great-tailed grackles, the Mexican duck, and curved-billed thrashers and the first survey of wild birds in Mexico.

Recombinant TgHSP70 Immunization Protects against Toxoplasma gondii Brain Cyst Formation by Enhancing Inducible Nitric Oxide Expression

Directory of Open Access Journals (Sweden)

Neide M. Silva

2017-04-01

Full Text Available Toxoplasma gondii is known to cause congenital infection in humans and animals and severe disease in immunocompromised individuals; consequently development of vaccines against the parasite is highly necessary. Under stress conditions, T. gondii expresses the highly immunogenic heat shock protein 70 (TgHSP70. Here, we assessed the protective efficacy of rTgHSP70 immunization combined with Alum in oral ME-49 T. gondii infection and the mechanisms involved on it. It was observed that immunized mice with rTgHSP70 or rTgHSP70 adsorbed in Alum presented a significantly reduced number of cysts in the brain that was associated with increased iNOS+ cell numbers in the organ, irrespective the use of the adjuvant. Indeed, ex vivo experiments showed that peritoneal macrophages pre-stimulated with rTgHSP70 presented increased NO production and enhanced parasite killing, and the protein was able to directly stimulate B cells toward antibody producing profile. In addition, rTgHSP70 immunization leads to high specific antibody titters systemically and a mixed IgG1/IgG2a response, with predominance of IgG1 production. Nonetheless, it was observed that the pretreatment of the parasite with rTgHSP70 immune sera was not able to control T. gondii internalization and replication by NIH fibroblast neither peritoneal murine macrophages, nor anti-rTgHSP70 antibodies were able to kill T. gondii by complement-mediated lysis, suggesting that these mechanisms are not crucial to resistance. Interestingly, when in combination with Alum, rTgHSP70 immunization was able to reduce inflammation in the brain of infected mice and in parallel anti-rTgHSP70 immune complexes in the serum. In conclusion, immunization with rTgHSP70 induces massive amounts of iNOS expression and reduced brain parasitism, suggesting that iNOS expression and consequently NO production in the brain is a protective mechanism induced by TgHSP70 immunization, therefore rTgHSP70 can be a good candidate for

Toxoplasma gondii Actively Inhibits Neuronal Function in Chronically Infected Mice

Science.gov (United States)

Haroon, Fahad; Händel, Ulrike; Angenstein, Frank; Goldschmidt, Jürgen; Kreutzmann, Peter; Lison, Holger; Fischer, Klaus-Dieter; Scheich, Henning; Wetzel, Wolfram; Schlüter, Dirk; Budinger, Eike

2012-01-01

Upon infection with the obligate intracellular parasite Toxoplasma gondii, fast replicating tachyzoites infect a broad spectrum of host cells including neurons. Under the pressure of the immune response, tachyzoites convert into slow-replicating bradyzoites, which persist as cysts in neurons. Currently, it is unclear whether T. gondii alters the functional activity of neurons, which may contribute to altered behaviour of T. gondii–infected mice and men. In the present study we demonstrate that upon oral infection with T. gondii cysts, chronically infected BALB/c mice lost over time their natural fear against cat urine which was paralleled by the persistence of the parasite in brain regions affecting behaviour and odor perception. Detailed immunohistochemistry showed that in infected neurons not only parasitic cysts but also the host cell cytoplasm and some axons stained positive for Toxoplasma antigen suggesting that parasitic proteins might directly interfere with neuronal function. In fact, in vitro live cell calcium (Ca2+) imaging studies revealed that tachyzoites actively manipulated Ca2+ signalling upon glutamate stimulation leading either to hyper- or hypo-responsive neurons. Experiments with the endoplasmatic reticulum Ca2+ uptake inhibitor thapsigargin indicate that tachyzoites deplete Ca2+ stores in the endoplasmatic reticulum. Furthermore in vivo studies revealed that the activity-dependent uptake of the potassium analogue thallium was reduced in cyst harbouring neurons indicating their functional impairment. The percentage of non-functional neurons increased over time In conclusion, both bradyzoites and tachyzoites functionally silence infected neurons, which may significantly contribute to the altered behaviour of the host. PMID:22530040

A novel Toxoplasma gondii nuclear factor TgNF3 is a dynamic chromatin-associated component, modulator of nucleolar architecture and parasite virulence.

Directory of Open Access Journals (Sweden)

Alejandro Olguin-Lamas

2011-03-01

Full Text Available In Toxoplasma gondii, cis-acting elements present in promoter sequences of genes that are stage-specifically regulated have been described. However, the nuclear factors that bind to these cis-acting elements and regulate promoter activities have not been identified. In the present study, we performed affinity purification, followed by proteomic analysis, to identify nuclear factors that bind to a stage-specific promoter in T. gondii. This led to the identification of several nuclear factors in T. gondii including a novel factor, designated herein as TgNF3. The N-terminal domain of TgNF3 shares similarities with the N-terminus of yeast nuclear FK506-binding protein (FKBP, known as a histone chaperone regulating gene silencing. Using anti-TgNF3 antibodies, HA-FLAG and YFP-tagged TgNF3, we show that TgNF3 is predominantly a parasite nucleolar, chromatin-associated protein that binds specifically to T. gondii gene promoters in vivo. Genome-wide analysis using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq identified promoter occupancies by TgNF3. In addition, TgNF3 has a direct role in transcriptional control of genes involved in parasite metabolism, transcription and translation. The ectopic expression of TgNF3 in the tachyzoites revealed dynamic changes in the size of the nucleolus, leading to a severe attenuation of virulence in vivo. We demonstrate that TgNF3 physically interacts with H3, H4 and H2A/H2B assembled into bona fide core and nucleosome-associated histones. Furthermore, TgNF3 interacts specifically to histones in the context of stage-specific gene silencing of a promoter that lacks active epigenetic acetylated histone marks. In contrast to virulent tachyzoites, which express the majority of TgNF3 in the nucleolus, the protein is exclusively located in the cytoplasm of the avirulent bradyzoites. We propose a model where TgNF3 acts essentially to coordinate nucleolus and nuclear functions by modulating

Differential Roles for Inner Membrane Complex Proteins across Toxoplasma gondii and Sarcocystis neurona Development.

Science.gov (United States)

Dubey, Rashmi; Harrison, Brooke; Dangoudoubiyam, Sriveny; Bandini, Giulia; Cheng, Katherine; Kosber, Aziz; Agop-Nersesian, Carolina; Howe, Daniel K; Samuelson, John; Ferguson, David J P; Gubbels, Marc-Jan

2017-01-01

The inner membrane complex (IMC) of apicomplexan parasites contains a network of intermediate filament-like proteins. The 14 alveolin domain-containing IMC proteins in Toxoplasma gondii fall into different groups defined by their distinct spatiotemporal dynamics during the internal budding process of tachyzoites. Here, we analyzed representatives of different IMC protein groups across all stages of the Toxoplasma life cycle and during Sarcocystis neurona asexual development. We found that across asexually dividing Toxoplasma stages, IMC7 is present exclusively in the mother's cytoskeleton, whereas IMC1 and IMC3 are both present in mother and daughter cytoskeletons (IMC3 is strongly enriched in daughter buds). In developing macro- and microgametocytes, IMC1 and -3 are absent, whereas IMC7 is lost in early microgametocytes but retained in macrogametocytes until late in their development. We found no roles for IMC proteins during meiosis and sporoblast formation. However, we observed that IMC1 and IMC3, but not IMC7, are present in sporozoites. Although the spatiotemporal pattern of IMC15 and IMC3 suggests orthologous functions in Sarcocystis , IMC7 may have functionally diverged in Sarcocystis merozoites. To functionally characterize IMC proteins, we knocked out IMC7, -12, -14, and -15 in Toxoplasma . IMC14 and -15 appear to be involved in switching between endodyogeny and endopolygeny. In addition, IMC7, -12, and -14, which are all recruited to the cytoskeleton outside cytokinesis, are critical for the structural integrity of extracellular tachyzoites. Altogether, stage- and development-specific roles for IMC proteins can be discerned, suggesting different niches for each IMC protein across the entire life cycle. IMPORTANCE The inner membrane complex (IMC) is a defining feature of apicomplexan parasites key to both their motility and unique cell division. To provide further insights into the IMC, we analyzed the dynamics and functions of representative alveolin

Outbreak of caprine abortion by Toxoplasma gondii in Midwest Brazil

Directory of Open Access Journals (Sweden)

Flávio Henrique Bravim Caldeira

2011-11-01

Full Text Available An outbreak of abortion by Toxoplasma gondii in goats on a farm in the Brazilian Midwest is reported. Gross lesions were not observed in seven aborted fetuses submitted to the Veterinary Pathology Laboratory, Federal University of Mato Grosso, for necropsy investigation. The main histologic lesions were mononuclear cell pneumonia and necrotizing encephalitis in varying degrees of intensity. PCR for Brucella abortus and Neospora caninum and aerobic cultures were negative in all cases. Antibody titles against T. gondii varying from 1:1024 to 1:32.768 were detected in serum samples from four aborted goats. Nested-PCR assay for T. gondii were positive in brain samples of all cases submitted. These findings indicate that T. gondii infection should be considered in the diagnosis of abortion in goats in Midwest Brazil.

Prevalence of Toxoplasma gondii in common moles (Talpa europaea)

NARCIS (Netherlands)

Krijger, I.M.; Cornelissen, J.B.W.J.; Wisselink, H.J.; Meerburg, B.G.

2014-01-01

Background The prevalence of Toxoplasma gondii in common moles, Talpa europaea, was investigated in order to determine whether moles can serve as an indicator species for T. gondii infections in livestock. Findings In total, 86 moles were caught from 25 different sites in the Netherlands. Five

Increased apoptosis skull of pups born to Toxoplasma gondii ...

African Journals Online (AJOL)

Background: Toxoplasma gondii is an intracellular obligate protozoan parasite that infects most warm-blooded animals including humans. It can cause congenital infection with clinical symptoms ranging from mild to severe including microcephaly. At the cellular level, infection T. gondii causes apoptosis in some tissues and ...

Prevalence of Toxoplasma gondii and Toxocara canis among Patients with Uveitis.

Science.gov (United States)

Lim, Su Jin; Lee, Sang Eun; Kim, Sun Hyun; Hong, Sung-Hee; You, Yong Sung; Kwon, Oh Woong; Kim, Hyeun Seung

2015-04-01

To investigate the prevalence of Toxoplasma gondii and Toxocara canis in patients with uveitis. Patients with uveitis were examined. Serum antibodies to T. gondii and T. canis were tested by using the enzyme-linked immunosorbent assay. Polymerase chain reaction (PCR) was done using blood and aqueous humor (AH). Ninety-eight patients were enrolled. Mean age was 43.5 ± 13.2 years. Six patients were seropositive for T. gondii with the following pattern: anterior uveitis, 1; posterior uveitis with retinitis, 2; pan uveitis, 2. One patient had a positive PCR result for T. gondii in AH, who showed panuveitis. Twenty-three patients were positive to serum IgG for T. canis with the following clinical manifestation: granuloma, 6; pigmented scar, 3; vitritis, 6--but none were PCR positive. T. gondii and T. canis are still important causes of uveitis. Ocular toxocariasis is not an uncommon cause of uveitis, even in adults.

THE ROLE OF HORMONES ON Toxoplasma gondii INFECTION: A SYSTEMATIC REVIEW

Directory of Open Access Journals (Sweden)

María De La Luz Galván-Ramírez

2014-10-01

Full Text Available Background: Toxoplasma gondii is the causal agent of toxoplasmosis in which one third of the world’s population has been infected. In pregnant women, it may cause abortion and severe damage to the fetal central nervous system. During pregnancy, the prevalence of toxoplasmosis increases throughout the second and third quarter of gestation, simultaneously progesterone and 17β-estradiol also increase. Thus, it has been suggested that these hormones can aggravate or reduce parasite reproduction. The aim of this study was reviewing the relationship between hormones and infection caused by T. gondii in several experimental animal models and humans, focused mainly on: a congenital transmission, b parasite reproduction, c strain virulence, d levels of hormone in host induced by T. gondii infection and e participation of hormone receptors in Toxoplasma gondii infection.Are the hormones specific modulators of T. gondii infection?A systematic review methodology was used to consult several databases (Pub Med, Lilacs, Medline, Science direct, Scielo, Ebsco, Sprinker, Wiley and Google Scholar dated from September, 2013 to March, 2014. Results: 30 studies were included; eight studies in humans and 22 in animals and cell cultures. In the human studies, the most studied hormones were testosterone, progesterone, prolactin and 17-ß estradiol. Type I (RH and BK and Type II (Prugniaud, SC, ME49,T45, P78 and T38 were the most frequent experimental strains. Conclusions: Thirty-five years have passed since the first studies regarding Toxoplasma gondii infection and its relationship with hormones. This systematic review suggests that hormones modulate Toxoplasma gondii infection in different animal models. However, given that data were not comparable, further studies are required to determine the mechanism of hormone action in the Toxoplasma gondii infectious process.

Seroprevalence of Toxoplasma gondii and potential risk factors in ...

African Journals Online (AJOL)

Toxoplasma gondii infection is important in pigs and humans may get infected through the consumption of undercooked infected pork. This study conducted in Oyo state, Nigeria for 15 months (between February, 2012 and April, 2013) investigated the seroprevalence of Toxoplasma gondii infection in pigs reared on farms ...

On the determination of Toxoplasma gondii virulence in mice

Science.gov (United States)

Toxoplasma gondii is one of the most successful pathogens on earth, capable of infecting mammals and birds. Numerous papers and reports are published on isolation of T .gondii from various natural sources worldwide. The house mouse (Mus musculus) has been used as the laboratory animal model to deter...

Toxoplasma gondii: biochemical and biophysical characterization of recombinant soluble dense granule proteins GRA2 and GRA6.

Science.gov (United States)

Bittame, Amina; Effantin, Grégory; Pètre, Graciane; Ruffiot, Pauline; Travier, Laetitia; Schoehn, Guy; Weissenhorn, Winfried; Cesbron-Delauw, Marie-France; Gagnon, Jean; Mercier, Corinne

2015-03-27

The most prominent structural feature of the parasitophorous vacuole (PV) in which the intracellular parasite Toxoplasma gondii proliferates is a membranous nanotubular network (MNN), which interconnects the parasites and the PV membrane. The MNN function remains unclear. The GRA2 and GRA6 proteins secreted from the parasite dense granules into the PV have been implicated in the MNN biogenesis. Amphipathic alpha-helices (AAHs) predicted in GRA2 and an alpha-helical hydrophobic domain predicted in GRA6 have been proposed to be responsible for their membrane association, thereby potentially molding the MMN in its structure. Here we report an analysis of the recombinant proteins (expressed in detergent-free conditions) by circular dichroism, which showed that full length GRA2 displays an alpha-helical secondary structure while recombinant GRA6 and GRA2 truncated of its AAHs are mainly random coiled. Dynamic light scattering and transmission electron microscopy showed that recombinant GRA6 and truncated GRA2 constitute a homogenous population of small particles (6-8 nm in diameter) while recombinant GRA2 corresponds to 2 populations of particles (∼8-15 nm and up to 40 nm in diameter, respectively). The unusual properties of GRA2 due to its AAHs are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

Toxoplasma gondii in Blood Donors: A Study in Boyer-Ahmad County, Southwest Iran

Directory of Open Access Journals (Sweden)

Abdolali Moshfe

2018-01-01

Full Text Available Toxoplasma gondii is an important foodborne protozoan that can be transmitted through infected blood containing tachyzoite form of the parasite. The current study aimed to evaluate the prevalence of T. gondii infection and related risk factors among healthy blood donors in Boyer-Ahmad County, southwest Iran. Blood samples were taken from 285 healthy blood donors who voluntarily agreed to participate in this study. Sera and buffy coat were isolated from the blood samples for serological and molecular evaluations. The sera were tested for anti-T. gondii antibodies (both IgG and IgM, using a commercial ELISA kit. The buffy coat of seropositive cases was evaluated for detection of T. gondii DNA by PCR. Moreover, a structured questionnaire, containing socioepidemiological data and possible risk factors, was filled out by each participant during sample collection. Anti-T. gondii antibodies were detected in sera of 48/285 (16.8% participants. Only two of the subjects (0.7% were seropositive for both IgG and IgM antibodies. T. gondii DNA was not detected in buffy coat of any of the seropositive cases. Risk factors such as contact with soil (OR, 9.7; 95% CI, 4.9–19.4 and consumption of semicooked meat (OR, 2.5; 95% CI, 1.2–5.03 were statistically associated with seropositivity to T. gondii. The seroprevalence rate of T. gondii antibodies in the blood donors of Boyer-Ahmad County was not high in comparison with other regions in Iran. In this study, consumption of undercooked meats, job, and contact with soil were independent risk factors associated with T. gondii infection, which can be considered as potential sources of T. gondii infection.

Seroprevalence of Anti-Toxoplasma gondii Antibodies Among Lebanese Pregnant Women.

Science.gov (United States)

Nahouli, Hasan; El Arnaout, Nour; Chalhoub, Elias; Anastadiadis, Elie; El Hajj, Hiba

2017-12-01

Toxoplasma gondii, the causative agent of toxoplasmosis, is a zoonotic obligate intracellular protozoan parasite responsible for the infection of almost one-third of the world's population. T. gondii is particularly threatening for primo-infected pregnant women and may lead, following vertical transplacental transmission, to spontaneous abortion, miscarriage, or severe manifestations in the newborn. The aim of this study was to provide an updated estimate of the seroprevalence of anti-T. gondii antibodies among a group of Lebanese pregnant women and its seroconversion rate. This is a retrospective cohort study, in which medical records of 11,000 pregnant women were screened. These women visited a private Obstetrics and Gynecology clinic located in Beirut, the capital of Lebanon, during the period of January 1994 till September 2015. Serological results of anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) results of 2456 Lebanese pregnant women who fulfilled the inclusion criteria were included in the analysis. Seropositivity and seroconversion rates for women with repeated tests were reported according to age and area of residence. The overall anti-T. gondii IgG and IgM seropositivity among 2456 Lebanese pregnant women was 82.6% and 1.8% respectively. The highest IgG seropositivity is among the age group of 35-44 years (87.81%) and at the governorate of "Mount Lebanon" (82.95%). Sixty-four seroconversions were detected and two abortions due to T. gondii infection during pregnancy were recorded. The seroprevalence of anti-T. gondii IgG among the screened pregnant women in Lebanon is the highest in the Arab region. These results highlight the importance of running a national sample survey to estimate the real potential burden of this infection and its impact on maternal and fetal health.

Prevalence of encysted Toxoplasma gondii in raptors from Alabama.

Science.gov (United States)

Lindsay, D S; Smith, P C; Hoerr, F J; Blagburn, B L

1993-12-01

Little is known about the prevalence of encysted Toxoplasma gondii in wild birds. We examined the hearts and breast muscles from 101 raptors for encysted T. gondii. All of the raptors had been submitted for necropsy to the State Veterinary Diagnostic Laboratory, Auburn, Alabama. Tissues were digested in acid-pepsin solution and inoculated into groups of 3-5 laboratory mice. Toxoplasma gondii was isolated from 27 of 101 (26.7%) raptors: 8 of 12 (66.7%) red-shouldered hawks (Buteo lineatus), 13 of 27 (41.1%) red-tailed hawks (Buteo jamaicensis), 1 of 4 (25%) Cooper's hawks (Accipiter cooperi), 1 of 5 (20%) great horned owls (Bubo virginianus), 4 of 15 (26.7%) barred owls (Strix varia), and 1 of 3 (33.3%) kestrels (Falco sparverius). Toxoplasma gondii was not isolated from 3 broad-winged hawks (Buteo platypterus), 3 sharp-shinned hawks (Accipiter striatus), 6 barn owls (Tyto alba), 9 screech owls (Asio otus), a Mississippi kite (Ictinia misisippiensis), 2 golden eagles (Aquila chrysaetos), a bald eagle (Haliaeetus leucocephalus), 4 ospreys (Pandion haliaetus), 4 turkey vultures (Cathartes aura), or 2 black vultures (Coragyps atratus). No significant difference (P > 0.05) in prevalence was detected based on sex using chi-square analysis. Chi-square analysis of the data demonstrated that adult raptors had encysted stages of T. gondii significantly (P < 0.05) more often than did immature raptors.

Non-association between anti-Toxoplasma gondii antibodies and ABO blood group system

Directory of Open Access Journals (Sweden)

ACF Rodrigues

2011-01-01

Full Text Available Toxoplasma gondii infects humans through the gastrointestinal tract (GIT, which elicits humoral immune response with specific antibodies. The expression of the ABO blood group glycoconjugates also occurs in this same system and may influence the human susceptibility of infection by T. gondii. The aim of the present study was to investigate the association between ABO blood group phenotypes and the presence of anti-T. gondii antibodies. Data - including age, results of serology tests for T. gondii infection and ABO blood group phenotypes - were assembled from the medical records of 1,006 pregnant women attended in the Base Hospital of the Medical School of São José do Rio Preto, Brazil, between 2001 and 2004. The chi-square test was used to compare the results with the level of significance set at 5%. Of the studied cases, 64.1% (645/1006 and 35.9% (391/1006 presented respectively positive and negative serology tests for anti-T. gondii antibodies. The mean age of those who tested positive was higher than those with negative serology tests (p = 0.0004. The frequencies of ABO blood group phenotypes were similar in those with and without anti-T. gondii antibodies (p = 0.35. In conclusion, the ABO blood group system is not associated with the presence or absence of anti-T. gondii antibodies.

Toxoplasma gondii infection in interstate truck drivers: a case-control seroprevalence study.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Pacheco-Vega, Sandy Janet; Hernández-Tinoco, Jesús; Salcedo-Jáquez, Misael; Sánchez-Anguiano, Luis Francisco; Berumen-Segovia, Luis Omar; Rábago-Sánchez, Elizabeth; Liesenfeld, Oliver

2015-02-05

Infection with Toxoplasma gondii can be acquired via the ingestion of undercooked or raw meat containing tissue cysts, or via ingestion of water contaminated with oocysts. Professional long distance truck driving may have epidemiological importance for food-borne infections since drivers eat out of home and in places where hygiene and cooking practices are uncertain. We aimed to determine whether interstate truck drivers in Durango, Mexico have an increased risk of infection with T. gondii as indicated by seropositivity; and to determine the socio-demographic, work, clinical, and behavioral characteristics associated with T. gondii seropositivity in interstate truck drivers. Through a case-control study design, 192 truck drivers and 192 controls from the general population of the same region matched by gender and age were examined with enzyme-linked immunoassays for the presence of anti-Toxoplasma IgG and IgM antibodies. Socio-demographic, work, clinical and behavioral characteristics from the truck drivers were obtained. Anti-T. gondii IgG antibodies were found in 23 (12.0%) of 192 truck drivers and in 13 (6.8%) of 192 controls (OR = 21.0; 95% CI: 1.23-358.38; P = 0.002). Anti-T. gondii IgM antibodies were found in 7 (3.6%) cases and in 7 (3.6%) controls (P = 1.00). The seroprevalence of T. gondii infection was higher in drivers with reflex impairment than in those without this impairment (4/13, 30.8% vs 19/179, 10.6%, respectively; P = 0.05), and in drivers with hearing impairment than in those without this impairment (3/7, 42.9% vs 20/185, 10.8%, respectively; P = 0.03). Multivariate analysis of work and behavioral characteristics of truck drives showed positive associations of T. gondii exposure with trips to the south of Mexico (OR = 3.11; 95% CI: 1.02-9.44; P = 0.04) and consumption of horse meat (OR = 5.18; 95% CI: 1.62-16.55; P = 0.005). Results suggest that interstate truck drivers may have an increased risk for T

Prevalence of Toxoplasma gondii infection in HIV-infected patients and food animals and direct genotyping of T. gondii isolates, Southern Ghana.

Science.gov (United States)

Pappoe, Faustina; Cheng, Weisheng; Wang, Lin; Li, Yuanling; Obiri-Yeboah, Dorcas; Nuvor, Samuel Victor; Ambachew, Henock; Hu, Xiaodong; Luo, Qingli; Chu, Deyong; Xu, Yuanhong; Shen, Jilong

2017-06-01

Toxoplasma gondii is of public health and veterinary importance causing severe diseases in immunocompromised individuals including HIV/AIDS patients and in congenital cases and animals. There is limited information on the epidemiology of T. gondii infection in humans, particularly HIV patients and food animals and the parasite genotypes in Ghana. A total of 394 HIV-infected patients from three hospitals were screened for T. gondii anti-IgG and IgM using ELISA. DNAs from blood samples of seropositve participants and 95 brain tissues of food animals were PCR assayed to detect Toxoplasma gra6. DNA positive samples were genotyped using multilocus nested polymerase chain reaction restriction fragment length polymorphism at 10 loci: sag1, alt.sag2, sag3, btub, gra6, l358, c22-8, c29-2, pk1, and apico. The overall seroprevalence was 74.37% (293/394). Toxoplasma DNAs were detected in 3.07% of the seropositive participants and 9.47% of the animals. Six of the human DNA positive samples were partly typed at sag3: 33.33, 50, and 16.67% isolates had type I, II, and III alleles, respectively. All nine isolates from food animals typed at nine loci except apico were atypical: six isolates were identical to ToxoDB #41 and #145, and one was identical to TgCkBrRj2 all identified in Brazil. The genotype of two isolates has not been reported previously and was named as TgCtGh1. T. gondii seroprevalence is high among the HIV-infected individuals with T. gondii circulating in Ghana being genetically diverse.

Use of filter papers to determine seroprevalence of Toxoplasma gondii among hunted ungulates

Science.gov (United States)

Toxoplasmosis is a zoonosis caused by the protozoan Toxoplasma gondii, and it is found worldwide. To determine whether ungulates are reservoirs of T. gondii in an isolated and remote region of the northeastern Peruvian Amazon, antibodies to T. gondii were determined in 5 species of ungulates by the...

Isolation and genetic characterization of Toxoplasma gondii from the gray wolf Canis lupus

Science.gov (United States)

Little is known of the genetic diversity of Toxoplasma gondii circulating in wildlife. In the present study feral gray wolf (Canis lupus) from Minnesota were examined for T. gondii infection. Antibodies to T. gondii were detected in 130 (52.4%) of 248 wolves tested by the modified agglutination test...

Seroepidemiology of Toxoplasma gondii infection in pregnant women in a public hospital in northern Mexico

Directory of Open Access Journals (Sweden)

Díaz-García Juan

2006-07-01

Full Text Available Abstract Background Toxoplasma gondii (T. gondii infection in pregnant women represents a risk for congenital disease. There is scarce information about the epidemiology of T. gondii infection in pregnant women in Mexico. Therefore, we sought to determine the prevalence of T. gondii infection and associated socio-demographic, clinical and behavioural characteristics in a population of pregnant women of Durango City, Mexico. Methods Three hundred and forty three women seeking prenatal care in a public hospital of Durango City in Mexico were examined for T. gondii infection. All women were tested for anti-T. gondii IgM and IgG antibodies by using IMx Toxo IgM and IMx Toxo IgG 2.0 kits (Abbott Laboratories, Abbott Park, IL, USA, respectively. Socio-demographic, clinical and behavioural characteristics from each participant were also obtained. Results Twenty one out of the 343 (6.1% women had IgG anti-T. gondii antibodies. None of the 343 women had IgM anti-T. gondii antibodies. Multivariate analysis using logic regression showed that T. gondii infection was associated with living in a house with soil floor (adjusted OR = 7.16; 95% CI: 1.39–36.84, residing outside of Durango State (adjusted OR = 4.25; 95% CI: 1.72–10.49, and turkey meat consumption (adjusted OR = 3.85; 95% CI: 1.30–11.44. Other characteristics as cat contact, gardening, and food preferences did not show any association with T. gondii infection. Conclusion The prevalence of T. gondii infection in pregnant women of Durango City is low as compared with those reported in other regions of Mexico and the majority of other countries. Poor housing conditions as soil floors, residing in other Mexican States, and turkey meat consumption might contribute to acquire T. gondii infection.

Effects of ionizing radiation over the structure, metabolism and infectivity of a pathogenic protozoan, Toxoplasma gondii; Efeitos da radiacao ionizante sobre a estrutura, metabolismo e infectividade de um protozoario patogenico, Toxoplasma gondii (Nicole and Manceau, 1908)

Energy Technology Data Exchange (ETDEWEB)

Hiramoto, Roberto Mitsuyoshi

1998-07-01

The intracellular parasite Toxoplasma gondii (Apicomplexa), has as definitive host domestic and wild felines and as intermediate hosts most species of mammals and birds, Including man. The infection in man is usually asymptomatic, but can become a severe and lethal illness in some special groups like the fetus of primoinfected pregnant woman, or in AIDS and transplanted patients. The transmission is due to ingestion of food or water contaminated with oocysts from cat feces as well as raw or rare cooked cyst containing meet. There is no available vaccine against toxoplasmosis, with some reports of the use ionizing radiation in order to attenuate or suppress the parasite. These studies are promising, but more research is needed to optimize the radiation process and to clarify those alterations caused on T gondii.Using a increasing doses of {sup 60} Co irradiation on T.gondii tachyzoites, we studied many parameters such as morphology, both at optical and electron microscopy level, detection of DNA fragmentation, metabolism alterations (cellular oxidative burst, protein, nucleic acids and DNA synthesis), determination of the parasite survival both in in vivo and in vitro models, antigenicity and immunogenicity after the process, cellular invasion and irradiated tachyzoite induced protection. After definition of 200 Gy of {sup 60} Co irradiation as the lower radiation dose that suppress parasite growth in vitro and in vivo, we found no detectable changes in parasite viability, its cell invasion capacity or in its structural proteins. DNA fragmentation like apoptosis or alterations of the parasite metabolism were similarly not affected by radiation. Mice infection with irradiated parasites induce partial protection when these animals were re-inoculated with non irradiated virulent parasites, inducing greater specific IgG levels as well as a longer survival. Irradiated T.gondii maintains its the ability of invasion, even under radiation effects. Based on our results we

Anti-gluten immune response following Toxoplasma gondii infection in mice.

Directory of Open Access Journals (Sweden)

Emily G Severance

Full Text Available Gluten sensitivity may affect disease pathogenesis in a subset of individuals who have schizophrenia, bipolar disorder or autism. Exposure to Toxoplasma gondii is a known risk factor for the development of schizophrenia, presumably through a direct pathological effect of the parasite on brain and behavior. A co-association of antibodies to wheat gluten and to T. gondii in individuals with schizophrenia was recently uncovered, suggesting a coordinated gastrointestinal means by which T. gondii and dietary gluten might generate an immune response. Here, we evaluated the connection between these infectious- and food-based antigens in mouse models. BALB/c mice receiving a standard wheat-based rodent chow were infected with T. gondii via intraperitoneal, peroral and prenatal exposure methods. Significant increases in the levels of anti-gluten IgG were documented in all infected mice and in offspring from chronically infected dams compared to uninfected controls (repetitive measures ANOVAs, two-tailed t-tests, all p≤0.00001. Activation of the complement system accompanied this immune response (p≤0.002-0.00001. Perorally-infected females showed higher levels of anti-gluten IgG than males (p≤0.009 indicating that T. gondii-generated gastrointestinal infection led to a significant anti-gluten immune response in a sex-dependent manner. These findings support a gastrointestinal basis by which two risk factors for schizophrenia, T. gondii infection and sensitivity to dietary gluten, might be connected to produce the immune activation that is becoming an increasingly recognized pathology of psychiatric disorders.

Urine sample used for detection of toxoplasma gondii infection by loop-mediated isothermal amplification (LAMP).

Science.gov (United States)

Hu, Xin; Pan, Chang-Wang; Li, Ya-Fei; Wang, Han; Tan, Feng

2012-02-01

In this study, a loop-mediated isothermal amplification (LAMP) assay was established to detect Toxoplasma gondii DNA in mice infected with T. gondii PRU strain. This LAMP assay was based on the sequence of highly repetitive B1 gene. The detection limit of T. gondii LAMP assay was 1 pg of T. gondii DNA, which was evaluated using 10-fold serially diluted DNA of cultured parasites. The LAMP assay was also highly specific for T. gondii and able to detect T. gondii DNA in urine of mice treated with dexamethasone at 90 day post infection (p.i.), although this assay could not detect the DNA in mice urine 2-6 days p.i. These results demonstrated that LAMP is effective for evaluation of therapy effectiveness for T. gondii infection. The established LAMP assay may represent a useful and practical tool for the routine diagnosis and therapeutic evaluation of human toxoplasmosis.

ELISA-seroprevalence of Toxoplasma gondii in draught horses in Greater Cairo, Egypt.

Science.gov (United States)

Haridy, Fouad M; Shoukry, Nahla M; Hassan, Aly Awad; Morsy, Tosson A

2009-12-01

Toxoplasma gondii is one of the important zoonotic parasites of worldwide. In this paper the seroprevalence of T. gondii in draught horses (3-15 years) including 90 males and 10 females in the first half of the year 2009 was studied. The result showed that the overall ELISA-T. gondii antibodies were 25% of the horses in Greater Cairo, 50% (females) and 22.2% (males).

Calcium uptake and proton transport by acidocalcisomes of Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Peter Rohloff

Full Text Available Acidocalcisomes are acidic calcium stores found in diverse organisms, being conserved from bacteria to humans. They possess an acidic matrix that contains several cations bound to phosphates, which are mainly present in the form of short and long polyphosphate chains. Their matrix is acidified through the action of proton pumps such as a vacuolar proton ATPase and a vacuolar proton pyrophosphatase. Calcium uptake occurs through a Ca(2+/H(+ countertransporting ATPase located in the membrane of the organelle. Acidocalcisomes have been identified in a variety of microorganisms, including Apicomplexan parasites such as Plasmodium and Eimeria species, and in Toxoplasma gondii. We report the purification and characterization of an acidocalcisome fraction from T. gondii tachyzoites after subcellular fractionation and further discontinuous iodixanol gradient purification. Proton and calcium transport activities in the fraction were characterized by fluorescence microscopy and spectrophotometric methods using acridine orange and arsenazo III, respectively. This work will facilitate the understanding of the function of acidocalcisomes in Apicomplexan parasites, as we can now isolate highly purified fractions that could be used for proteomic analysis to find proteins that may clarify the biogenesis of these organelles.

Alterações cognitivas em ratos infectados com Toxoplasma gondii

OpenAIRE

Maia, Raquel da Silveira

2012-01-01

O Toxoplasma gondii é um protozoário parasito que induz alterações comportamentais em roedores. O objetivo do presente estudo foi avaliar o efeito da infecção pelo T.gondii durante a fase crônica na memória operacional e na impulsividade de roedores, bem como o efeito de antipsicóticos em reverter as eventuais alterações comportamentais decorrentes da infecção. Ratos wistar fêmeas (n=40) foram infectadas com 25 cistos da cepa ME-49 do T. gondii, após 4 meses os animais foram submetidos aos te...

Lack of association between Toxoplasma gondii infection and occupational exposure to animals

Science.gov (United States)

Pacheco-Vega, Sandy Janet; Hernández-Tinoco, Jesús; Saldaña-Simental, Diana Elizabeth; Sánchez-Anguiano, Luis Francisco; Salcedo-Jáquez, Misael; Ramos-Nevárez, Agar; Liesenfeld, Oliver; Márquez-Conde, José Ángel; Cerrillo-Soto, Sandra Margarita; Martínez-Ramírez, Lucio; Guido-Arreola, Carlos Alberto

2014-01-01

The association of infection with Toxoplasma gondii and occupational exposure to animals has been scantly determined. We performed a case-control study with 200 subjects from Durango Province, Mexico, occupationally exposed to animals and 200 age- and gender-matched subjects without this occupation. Sera from all participants were analyzed for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. The association of seroprevalence with sociodemographic, work, clinical, and behavioral characteristics in cases was determined. Cases and controls had similar frequencies of anti-T. gondii IgG antibodies (12/200: 6.0% and 11/200: 5.5%, respectively) (OR = 3.0; 95% CI: 0.12–73.64; P = 1.0). The frequency of sera with high (>150 IU/ml) levels of anti-T. gondii IgG antibodies was comparable among cases and controls (P = 0.61). Seroprevalence of anti-T. gondii IgM antibodies was similar in cases (4, 2.0%) than in controls (4, 2.0%) (P = 1.0). Multivariate analysis showed that seropositivity was associated with eating while working (OR = 7.14; 95% CI: 1.91–26.72; P = 0.003) and consumption of duck meat (OR = 5.43; 95% CI: 1.43–20.54; P = 0.01). No association between seropositivity to T. gondii and occupational exposure to animals was found. However, risk factors for infection found should be taken into account to reduce the exposure to T. gondii. PMID:25544890

Detection of soluble antigens of Toxoplasma gondii by a four-layer modification of an enzyme immunoassay.

Science.gov (United States)

Turunen, H J

1983-01-01

A sensitive four-layer modification of an enzyme immunoassay for the detection of soluble antigens of Toxoplasma gondii is described. Microtiter plates were sensitized with rabbit anti-toxoplasma immunoglobulins (6 micrograms/ml) used as the primary antibodies; guinea pig anti-toxoplasma immunoglobulins (6 micrograms/ml) were used as the secondary trapping antibodies. Horseradish peroxidase-conjugated anti-guinea pig immunoglobulins were used as the indicator antibodies. The specificity of the antigen assay was confirmed by using guinea pig immunoglobulins from preimmunization sera. The sensitivity of the antigen assay was found to be at least 10 ng of antigen protein per ml. The suitability of the method for detecting antigens of T. gondii in different specimens was studied by experimental toxoplasma infection in mice. Antigenic components of T. gondii could be detected in different tissue specimens from infected animals from the first day after infection onwards. Toxoplasma antigen in serum and urine samples from infected mice reached detectable levels on day 2 after infection followed by a linear increase in antigen concentration in succeeding samples. This method might offer a valuable aid for a rapid etiological diagnosis also in human cases of acute toxoplasmosis. PMID:6345574

Detection of toxoplasma gondii antigens in sera from experimentally infected mice

International Nuclear Information System (INIS)

Shojaee, S.; Keshavarz, H.; Rezaian, M.; Mohebali, M.

2007-01-01

Detection of Toxoplasma antigen in serum of mice by Immunoblotting. strain. IgG isolated from rabbits that were immunized with T. gondii Immunoblotting was performed to detect T. gondii antigens in sera of mice. Serum samples from mice experimentally infected with T. gondii RH strain. The value of Immunoblotting in diagnosis of toxoplasmosis in acute stage of infection. The antigen bands detected in serum sample of mice were experimentally infected with T. gondii tachyzoite in immunoblotting. Six bands demonstrated on seventh post infection day six bands were identified. Similarly on sixth day four bands, on day five three bands and on fourth post infection day two bands were identified. No band was detected in control group sera. Immunoblotting is a sensitive method for diagnosis of acute stage of toxoplasmosis. (author)

The malaria parasite RhopH protein complex interacts with erythrocyte calmyrin identified from a comprehensive erythrocyte protein library.

Science.gov (United States)

Miura, Toyokazu; Takeo, Satoru; Ntege, Edward H; Otsuki, Hitoshi; Sawasaki, Tatsuya; Ishino, Tomoko; Takashima, Eizo; Tsuboi, Takafumi

2018-06-02

Malaria merozoite apical organelles; microneme and rhoptry secreted proteins play functional roles during and following invasion of host erythrocytes. Among numerous proteins, the rhoptries discharge high molecular weight proteins known as RhopH complex. Recent reports suggest that the RhopH complex is essential for growth and survival of the malaria parasite within erythrocytes. However, an in-depth understanding of the host-parasite molecular interactions is indispensable. Here we utilized a comprehensive mouse erythrocyte protein library consisting of 443 proteins produced by a wheat germ cell-free system, combined with AlphaScreen technology to identify mouse erythrocyte calmyrin as an interacting molecule of the rodent malaria parasite Plasmodium yoelii RhopH complex (PyRhopH). The PyRhopH interaction was dependent on the calmyrin N-terminus and divalent cation capacity. The finding unveils a recommendable and invaluable usefulness of our comprehensive mouse erythrocyte protein library together with the AlphaScreen technology in investigating a wide-range of host-parasite molecular interactions. Copyright © 2018 Elsevier Inc. All rights reserved.

Toxoplasma gondii IgG antibodies in HIV/AIDS patients attending ...

African Journals Online (AJOL)

Background: Toxoplasmosis is caused by Toxoplasma gondii, a parasite that gradually evolved to be the most opportunistic parasite that complicates the course of HIV/AIDS in developing countries. Aim: This study was undertaken to investigate the presence of Toxoplasma gondii IgG antibodies in HIVinfected patients ...

Effects of ionizing radiation over the structure, metabolism and infectivity of a pathogenic protozoan, Toxoplasma gondii

International Nuclear Information System (INIS)

Hiramoto, Roberto Mitsuyoshi

1998-01-01

The intracellular parasite Toxoplasma gondii (Apicomplexa), has as definitive host domestic and wild felines and as intermediate hosts most species of mammals and birds, Including man. The infection in man is usually asymptomatic, but can become a severe and lethal illness in some special groups like the fetus of primoinfected pregnant woman, or in AIDS and transplanted patients. The transmission is due to ingestion of food or water contaminated with oocysts from cat feces as well as raw or rare cooked cyst containing meet. There is no available vaccine against toxoplasmosis, with some reports of the use ionizing radiation in order to attenuate or suppress the parasite. These studies are promising, but more research is needed to optimize the radiation process and to clarify those alterations caused on T gondii.Using a increasing doses of 60 Co irradiation on T.gondii tachyzoites, we studied many parameters such as morphology, both at optical and electron microscopy level, detection of DNA fragmentation, metabolism alterations (cellular oxidative burst, protein, nucleic acids and DNA synthesis), determination of the parasite survival both in in vivo and in vitro models, antigenicity and immunogenicity after the process, cellular invasion and irradiated tachyzoite induced protection. After definition of 200 Gy of 60 Co irradiation as the lower radiation dose that suppress parasite growth in vitro and in vivo, we found no detectable changes in parasite viability, its cell invasion capacity or in its structural proteins. DNA fragmentation like apoptosis or alterations of the parasite metabolism were similarly not affected by radiation. Mice infection with irradiated parasites induce partial protection when these animals were re-inoculated with non irradiated virulent parasites, inducing greater specific IgG levels as well as a longer survival. Irradiated T.gondii maintains its the ability of invasion, even under radiation effects. Based on our results we conclude that

Serological evidence of Toxoplasma gondii infection in captive marine mammals in Mexico.

Science.gov (United States)

Alvarado-Esquivel, C; Sánchez-Okrucky, R; Dubey, J P

2012-03-23

Toxoplasma gondii infection in marine mammals is important because they are considered as a sentinel for contamination of seas with T. gondii oocysts, and toxoplasmosis causes mortality in these animals, particularly sea otters. Serological evidence of T. gondii infection was determined in 75 captive marine mammals from four facilities in southern and central geographical regions in Mexico using the modified agglutination test (MAT). Antibodies (MAT, 1:25 or higher) to T. gondii were found in 55 (87.3%) of 63 Atlantic bottlenose dolphins (Tursiops truncatus truncatus), 3 of 3 Pacific bottlenose dolphins (Tursiops truncatus gillii), 2 of 4 California sea lions (Zalophus californianus), but not in 3 West Indian manatees (Trichechus manatus), and 2 Patagonian sea lions (Otaria flavescens). Seropositive marine mammals were found in all 4 (100%) facilities sampled. All marine mammals were healthy and there has not been any case of clinical toxoplasmosis in the facilities sampled for at least the last 15 years. The seroprevalence of T. gondii infection in marine mammals of the same species did not vary significantly with respect to sex and age. This is the first report on the detection of antibodies to T. gondii in marine mammals in Mexico. Published by Elsevier B.V.

LILRB4 Decrease on uDCs Exacerbate Abnormal Pregnancy Outcomes Following Toxoplasma gondii Infection

Directory of Open Access Journals (Sweden)

Shaowei Zhan

2018-03-01

Full Text Available Toxoplasma gondii (T. gondii infection in early pregnancy can result in miscarriage, dead fetus, and other abnormalities. The LILRB4 is a central inhibitory receptor in uterine dendritic cells (uDCs that plays essential immune-regulatory roles at the maternal–fetal interface. In this study, T. gondii-infected human primary uDCs and T. gondii-infected LILRB4-/- pregnant mice were utilized. The immune mechanisms underlying the role of LILRB4 on uDCs were explored in the development of abnormal pregnancy outcomes following T. gondii infection in vitro and in vivo. Our results showed that the expression levels of LILRB4 on uDCs from normal pregnant mice were obviously higher than non-pregnant mice, and peaked in mid-gestation. The LILRB4 expression on uDC subsets, especially tolerogenic subsets, from mid-gestation was obviously down-regulated after T. gondii infection and LILRB4 decrease could further regulate the expression of functional molecules (CD80, CD86, and HLA-DR or MHC II on uDCs, contributing to abnormal pregnancy outcomes. Our results will shed light on the molecular immune mechanisms of uDCs in abnormal pregnancy outcomes by T. gondii infection.

Seroprevalence and risk factors for Toxoplasma gondii infection in domestic cats in The Netherlands

NARCIS (Netherlands)

Opsteegh, M.; Haveman, R.; Swart, A.; Mensink-Beerepoot, M.E.; Hofhuis, A.; Langelaar, M.F.M.; van der Giessen, J.W.B.

2012-01-01

Cats, as definitive hosts, play an important role in the transmission of Toxoplasma gondii. To determine the seroprevalence and risk factors for T. gondii infection in Dutch domestic cats, serum samples of 450 cats were tested for T. gondii antibodies by indirect ELISA. Binary mixture analysis was

A novel multifunctional oligonucleotide microarray for Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Chen Feng

2010-10-01

Full Text Available Abstract Background Microarrays are invaluable tools for genome interrogation, SNP detection, and expression analysis, among other applications. Such broad capabilities would be of value to many pathogen research communities, although the development and use of genome-scale microarrays is often a costly undertaking. Therefore, effective methods for reducing unnecessary probes while maintaining or expanding functionality would be relevant to many investigators. Results Taking advantage of available genome sequences and annotation for Toxoplasma gondii (a pathogenic parasite responsible for illness in immunocompromised individuals and Plasmodium falciparum (a related parasite responsible for severe human malaria, we designed a single oligonucleotide microarray capable of supporting a wide range of applications at relatively low cost, including genome-wide expression profiling for Toxoplasma, and single-nucleotide polymorphism (SNP-based genotyping of both T. gondii and P. falciparum. Expression profiling of the three clonotypic lineages dominating T. gondii populations in North America and Europe provides a first comprehensive view of the parasite transcriptome, revealing that ~49% of all annotated genes are expressed in parasite tachyzoites (the acutely lytic stage responsible for pathogenesis and 26% of genes are differentially expressed among strains. A novel design utilizing few probes provided high confidence genotyping, used here to resolve recombination points in the clonal progeny of sexual crosses. Recent sequencing of additional T. gondii isolates identifies >620 K new SNPs, including ~11 K that intersect with expression profiling probes, yielding additional markers for genotyping studies, and further validating the utility of a combined expression profiling/genotyping array design. Additional applications facilitating SNP and transcript discovery, alternative statistical methods for quantifying gene expression, etc. are also pursued at

Brain cancer mortality rates increase with Toxoplasma gondii seroprevalence in France

Science.gov (United States)

Vittecoq, Marion; Elguero, Eric; Lafferty, Kevin D.; Roche, Benjamin; Brodeur, Jacques; Gauthier-Clerc, Michel; Missé, Dorothée; Thomas, Frédéric

2012-01-01

The incidence of adult brain cancer was previously shown to be higher in countries where the parasite Toxoplasma gondii is common, suggesting that this brain protozoan could potentially increase the risk of tumor formation. Using countries as replicates has, however, several potential confounding factors, particularly because detection rates vary with country wealth. Using an independent dataset entirely within France, we further establish the significance of the association between T. gondii and brain cancer and find additional demographic resolution. In adult age classes 55 years and older, regional mortality rates due to brain cancer correlated positively with the local seroprevalence of T. gondii. This effect was particularly strong for men. While this novel evidence of a significant statistical association between T. gondii infection and brain cancer does not demonstrate causation, these results suggest that investigations at the scale of the individual are merited.

Seroprevalence of Toxoplasma gondii in Danish farmed mink (Mustela vison S.)

DEFF Research Database (Denmark)

Henriksen, P; Dietz, H. H.; Uttenthal, Åse

1994-01-01

One hundred and ninety-five mink sera randomly selected from 17 Danish mink farms were evaluated for the presence of Toxoplasma gondii antibodies in the latex agglutination test. Six (3%) sera contained T. gondii antibodies in titres of 1:64 or more. The estimated 3% prevalence means that 300 000...... mink out of a total mink population of ten million might be infected with Toxoplasma gondii. This large number of possible sero-positive mink in Denmark indicates that there exists a potential risk of acquiring toxoplasmosis by pelting mink....

Sequence variation in TgROP7 gene among Toxoplasma gondii ...

African Journals Online (AJOL)

Yomi

2012-03-27

Mar 27, 2012 ... Toxoplasma gondii can infect a wide range of hosts including mammals and birds, causing toxoplasmosis which is one of the most common parasitic zoonoses worldwide. The present study examined sequence variation in rhoptry 7 (ROP7) gene among different T. gondii isolates from different hosts and ...

Detection of Toxolasma gondii in captive wild felids.

Science.gov (United States)

Buddhirongawatr, Ruangrat; Tungsudjai, Siriporn; Chaichoune, Kridsada; Sangloung, Charoonluk; Tantawiwattananon, Nitipan; Phonaknguen, Rassameepen; Sukthana, Yaowalark

2006-01-01

Toxoplasma gondii can infect all species of warm-blooded animals, including humans, and causes serious diseases in immunocompromized hosts. Live tachyzoites derived from serial passage in HeLa culture were used in the Sabin-Feldman dye test for detection of Toxoplasma gondii antibody in serum samples of 21 captive wild felids including one fishing cat (Prion nailurus viverrina), one leopard (Panthera pardus), two flat-headed cats (Prion nailurus planiceps), 6 tigers (Panthera tigris), two leopard cats (Felis bengalensis), two clouded leopards (Felis nebulosa), 3 pumas (Puma concolor), and 4 jungle cats (Felis chaus). Antibodies to Toxoplasma gondii were founded in 9 of 21 felids (42.8%). This study revealed that cell culture-derived tachyzoites can be used successfully as a source of live organisms in a gold standard Sabin-Feldman dye test, which is simpler, cheaper and less ethically sensitive than in vivo inoculation.

Isolation of Toxoplasma gondii from horse meat in Egypt.

Science.gov (United States)

Shaapan, R M; Ghazy, A A

2007-01-01

Portions of heart, liver, skeletal and diaphragmatic muscles obtained from 150 slaughtered horses at Giza-Zoo abattoir were used for bioassays in mice and cats. T. gondii tachyzoites were isolated successfully from the peritoneal exudates of the inoculated mice 6-8 days post inoculation with pooled horse tissues. Whereas, T. gondii tissue cysts containing bradyzoites were detected in the impression smears of mice brain on the 45th days or more post infection. The oocysts were detected in feces of cats 3-6 days post feeding on horse tissues containing tissue cysts. The oocysts became sporulated within 3-5 days in 2.5% Potassium dichromate. A total of 79 out of 150 horse meat samples were found to be infected with an incidence rate of 52.6 %. This is the first trial for isolation of T. gondii infective stages from horses in Egypt. Moreover, this study pointed out to the high infection rate of T. gondii in horse meat which may be considered as an important source of infection to wild zoo-animals in Egypt and humans in some countries if consumed raw or insufficiently cooked.

The structure of bradyzoite-specific enolase from Toxoplasma gondii reveals insights into its dual cytoplasmic and nuclear functions

Energy Technology Data Exchange (ETDEWEB)

Ruan, Jiapeng [Northwestern University, 320 E. Superior Street, Morton 7-601, Chicago, IL 60611 (United States); Mouveaux, Thomas [Université Lille Nord de France, (France); Light, Samuel H.; Minasov, George; Anderson, Wayne F. [Northwestern University, 320 E. Superior Street, Morton 7-601, Chicago, IL 60611 (United States); Tomavo, Stanislas [Université Lille Nord de France, (France); Ngô, Huân M., E-mail: h-ngo@northwestern.edu [Northwestern University, 320 E. Superior Street, Morton 7-601, Chicago, IL 60611 (United States); BrainMicro LLC, 21 Pendleton Street, New Haven, CT 06511 (United States)

2015-03-01

The second crystal structure of a parasite protein preferentially enriched in the brain cyst of T. gondii has been solved at 2.75 Å resolution. Bradyzoite enolase 1 is reported to have differential functions as a glycolytic enzyme and a transcriptional regulator in bradyzoites. In addition to catalyzing a central step in glycolysis, enolase assumes a remarkably diverse set of secondary functions in different organisms, including transcription regulation as documented for the oncogene c-Myc promoter-binding protein 1. The apicomplexan parasite Toxoplasma gondii differentially expresses two nuclear-localized, plant-like enolases: enolase 1 (TgENO1) in the latent bradyzoite cyst stage and enolase 2 (TgENO2) in the rapidly replicative tachyzoite stage. A 2.75 Å resolution crystal structure of bradyzoite enolase 1, the second structure to be reported of a bradyzoite-specific protein in Toxoplasma, captures an open conformational state and reveals that distinctive plant-like insertions are located on surface loops. The enolase 1 structure reveals that a unique residue, Glu164, in catalytic loop 2 may account for the lower activity of this cyst-stage isozyme. Recombinant TgENO1 specifically binds to a TTTTCT DNA motif present in the cyst matrix antigen 1 (TgMAG1) gene promoter as demonstrated by gel retardation. Furthermore, direct physical interactions of both nuclear TgENO1 and TgENO2 with the TgMAG1 gene promoter are demonstrated in vivo using chromatin immunoprecipitation (ChIP) assays. Structural and biochemical studies reveal that T. gondii enolase functions are multifaceted, including the coordination of gene regulation in parasitic stage development. Enolase 1 provides a potential lead in the design of drugs against Toxoplasma brain cysts.

"Latent" infection with Toxoplasma gondii: association with trait aggression and impulsivity in healthy adults.

Science.gov (United States)

Cook, Thomas B; Brenner, Lisa A; Cloninger, C Robert; Langenberg, Patricia; Igbide, Ajirioghene; Giegling, Ina; Hartmann, Annette M; Konte, Bettina; Friedl, Marion; Brundin, Lena; Groer, Maureen W; Can, Adem; Rujescu, Dan; Postolache, Teodor T

2015-01-01

Latent chronic infection with Toxoplasma gondii (T. gondii), a common neurotropic pathogen, has been previously linked with suicidal self-directed violence (SSDV). We sought to determine if latent infection with T. gondii is associated with trait aggression and impulsivity, intermediate phenotypes for suicidal behavior, in psychiatrically healthy adults. Traits of aggression and impulsivity were analyzed in relationship to IgG antibody seropositivity for T. gondii and two other latent neurotropic infections, herpes simplex virus 1 (HSV1) and cytomegalovirus (CMV). One thousand community-residing adults residing in the Munich metropolitan area with no Axis I or II conditions by SCID for DSM-IV (510 men, 490 women, mean age 53.6 ± 15.8, range 20-74). Plasma samples were tested for IgG antibodies to T. gondii, HSV-1 and CMV by ELISA. Self-reported ratings of trait aggression scores (Questionnaire for Measuring Factors of Aggression [FAF]) and trait impulsivity (Sensation-Seeking Scale-V [SSS-V]) were analyzed using linear multivariate methods. T. gondii IgG seropositivity was significantly associated with higher trait reactive aggression scores among women (p impulsive sensation-seeking (SSS-V Disinhibition) among younger men (p impulsivity, personality traits considered as endophenotypes for SSDV, are associated with latent T. gondii infection in a gender and age-specific manner, and could be further investigated as prognostic and treatment targets in T. gondii-positive individuals at risk for SSDV. Published by Elsevier Ltd.

First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico.

Science.gov (United States)

Torres-Castro, M; Noh-Pech, H; Puerto-Hernández, R; Reyes-Hernández, B; Panti-May, A; Hernández-Betancourt, S; Yeh-Gorocica, A; González-Herrera, L; Zavala-Castro, J; Puerto, F I

2016-01-01

Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico.

Concentration and retention of Toxoplasma gondii surrogates from seawater by red abalone (Haliotis rufescens)

Science.gov (United States)

Schott, Kristen C; Krusor, Colin; Tinker, M. Tim; Moore, James G.; Conrad, Patricia A.; Shapiro, Karen

2016-01-01

Small marine snails and abalone have been identified as high- and low-risk prey items, respectively, for exposure of threatened southern sea otters to Toxoplasma gondii, a zoonotic parasite that can cause fatal encephalitis in animals and humans. While recent work has characterized snails as paratenic hosts for T. gondii, the ability of abalone to vector the parasite has not been evaluated. To further elucidate why abalone predation may be protective against T. gondii exposure, this study aimed to determine whether: (1) abalone are physiologically capable of acquiring T. gondii; and (2) abalone and snails differ in their ability to concentrate and retain the parasite. Abalone were exposed to T. gondii surrogate microspheres for 24 h, and fecal samples were examined for 2 weeks following exposure. Concentration of surrogates was 2–3 orders of magnitude greater in abalone feces than in the spiked seawater, and excretion of surrogates continued for 14 days post-exposure. These results indicate that, physiologically, abalone and snails can equally vector T. gondii as paratenic hosts. Reduced risk of T. gondii infection in abalone-specializing otters may therefore result from abalone's high nutritional value, which implies otters must consume fewer animals to meet their caloric needs.

Concentration and retention of Toxoplasma gondii surrogates from seawater by red abalone (Haliotis rufescens).

Science.gov (United States)

Schott, Kristen C; Krusor, Colin; Tinker, M Tim; Moore, James; Conrad, Patricia A; Shapiro, Karen

2016-11-01

Small marine snails and abalone have been identified as high- and low-risk prey items, respectively, for exposure of threatened southern sea otters to Toxoplasma gondii, a zoonotic parasite that can cause fatal encephalitis in animals and humans. While recent work has characterized snails as paratenic hosts for T. gondii, the ability of abalone to vector the parasite has not been evaluated. To further elucidate why abalone predation may be protective against T. gondii exposure, this study aimed to determine whether: (1) abalone are physiologically capable of acquiring T. gondii; and (2) abalone and snails differ in their ability to concentrate and retain the parasite. Abalone were exposed to T. gondii surrogate microspheres for 24 h, and fecal samples were examined for 2 weeks following exposure. Concentration of surrogates was 2-3 orders of magnitude greater in abalone feces than in the spiked seawater, and excretion of surrogates continued for 14 days post-exposure. These results indicate that, physiologically, abalone and snails can equally vector T. gondii as paratenic hosts. Reduced risk of T. gondii infection in abalone-specializing otters may therefore result from abalone's high nutritional value, which implies otters must consume fewer animals to meet their caloric needs.

Toxoplasma gondii in horse meat intended for human consumption in Romania.

Science.gov (United States)

Paştiu, Anamaria Ioana; Györke, Adriana; Kalmár, Zsuzsa; Bolfă, Pompei; Rosenthal, Benjamin Martin; Oltean, Miruna; Villena, Isabelle; Spînu, Marina; Cozma, Vasile

2015-09-15

The prevalence of Toxoplasma gondii, an economically important zoonotic protozoan, was investigated in horses slaughtered for export and human consumption in the North of Romania. Pairs of samples, sera and heart tissues, were collected from 82 slaughtered horses. Examination of horse sera by ELISA at a dilution of 1:10, and by modified agglutination test (MAT) at a dilution of 1:6, revealed that 32 (39%) and 31(37.8%) horses, respectively, had antibodies against T. gondii. Using polymerase chain reaction (PCR) analysis, T. gondii DNA was not found in any heart sample collected from horses. By bioassay in mice, we obtained viable isolates of T. gondii from two of ten horses determined to be strongly positive by serological assay/ELISA. The prevalence estimated in horses highlighted the potential risk for human contamination by consumption of raw or undercooked meat. Copyright © 2015 Elsevier B.V. All rights reserved.

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).

Antibody Detection, Isolation, Genotyping, and Virulence of Toxoplasma gondii in Captive Felids from China

Directory of Open Access Journals (Sweden)

Yu-Rong Yang

2017-07-01

Full Text Available The felids are the only definitive hosts of Toxoplasma gondii, which could excrete oocysts into the environment and provide an infection source for toxoplasmosis in various warm-blooded animal species, particularly the captive felids that live close to human communities. The infection rate of the captive felids is a perfect standard in detecting the presence of Toxoplasma gondii oocysts in the environment. In this study, sera or tissue samples from zoo (1 young tiger, 2 adult tigers, 6 young lions, farm (10 masked palm civets, and pet hospital (28 cats from Henan Province (China were collected. The sera (n = 47 were tested for immunoglobulin G (IgG antibodies against T. gondii by using modified agglutination test (MAT, whereas the hearts tissue (n = 40 were bioassayed in mice to isolate T. gondii strains. The genotype was distinguished by using PCR-RFLP of 10 loci (SAG1, SAG2, SAG3, GRA6, BTUB, L358, c22-8, PK1, c29-2, and Apico. The detection rate for the T. gondii antibody in captive felids was 21.3% (10/47. One viable T. gondii strain (TgCatCHn4 was obtained from a cat heart tissue, and its genotype was ToxoDB#9. The oocysts of ToxoDB#9 were collected from a T. gondii-free cat. The virulence of TgCatCHn4 was low and no cysts were detected in the brain of mice at 60 days post-inoculation. The finding of the present study suggested a widespread exposure of T. gondii for felids in Henan Province of central China, particularly those from the zoological gardens and homes. ToxoDB#9 was the predominant strain in China. Preventive measures against T. gondii oocyst contamination of various components of the environment should thus be implemented, including providing pre-frozen meat, well-cooked cat food, cleaned fruits and vegetables, monitoring birds and rodents, inactive T. gondii oocysts in felids feces, and proper hygiene.

Insect-cell expression, crystallization and X-ray data collection of the bradyzoite-specific antigen BSR4 from Toxoplasma gondii

International Nuclear Information System (INIS)

Grujic, Ognjen; Grigg, Michael E.; Boulanger, Martin J.

2008-01-01

Preliminary X-ray diffraction studies of the bradyzoite-specific surface antigen BSR4 from T. gondii are described. Toxoplasma gondii is an important global pathogen that infects nearly one third of the world’s adult population. A family of developmentally expressed structurally related surface-glycoprotein adhesins (SRSs) mediate attachment to and are utilized for entry into host cells. The latent bradyzoite form of T. gondii persists for the life of the host and expresses a distinct family of SRS proteins, of which the bradyzoite-specific antigen BSR4 is a prototypical member. Structural studies of BSR4 were initiated by first recombinantly expressing BSR4 in insect cells, which was followed by crystallization and preliminary X-ray data collection to 1.95 Å resolution. Data processing showed that BSR4 crystallized with one molecule in the asymmetric unit of the P4 1 2 1 2 or P4 3 2 1 2 space group, with a solvent content of 60% and a corresponding Matthews coefficient of 2.98 Å 3 Da −1

Detection of Toxoplasma gondii DNA in Brazilian oysters (Crassostrea rhizophorae).

Science.gov (United States)

Ribeiro, L A; Santos, L K N S S; Brito, P A; Maciel, B M; Da Silva, A V; Albuquerque, G R

2015-05-04

The aim of this study was to detect evidence of Toxoplasma gondii using polymerase chain reaction (PCR)-based techniques in oysters (Crassostrea rhizophorae) obtained from the southern coastal region of Bahia, Brazil. A total of 624 oysters were collected, and the gills and digestive glands were dissected. Each tissue sample was separated into pools containing tissues (of the same type) from three animals, leading to a total of 416 experimental samples for analysis (208 samples each from the gills and digestive glands). Molecular analysis using PCR-based detection of the T. gondii AF 146527 repetitive fragment yielded negative results for all samples. However, when nested-PCR was used for detection of the T. gondii SAG-1 gene, 17 samples were positive, with the gills being the tissue with maximal detection of the parasite. These positive results were confirmed by sample sequencing. It is therefore suggested that C. rhizophorae oysters are capable of filtering and retaining T. gondii oocysts in their tissue. This represents a risk to public health because they are traditionally ingested in natura.

Seroprevalence of Toxoplasma gondii infection in feral cats in Qatar.

Science.gov (United States)

Boughattas, Sonia; Behnke, Jerzy; Sharma, Aarti; Abu-Madi, Marawan

2017-01-18

Cats are essential in the life cycle of Toxoplasma gondii as they can shed the environmentally resistant oocysts after acquiring infection. Human populations living in cities with high densities of feral cats are therefore likely to be at risk of infection. The current study is the first to estimate the seroprevalence of T. gondii in the feral cat population in Qatar. We investigated the seroprevalence of T. gondii among 495 adult cats from urban and suburban districts in Qatar. Using results from the Modified Agglutination Test, we fitted statistical models with host sex, area and season as explanatory factors and seropositivity as the outcome. The analysis revealed an overall seroprevalence of 82%. Seroprevalence was significantly higher in the summer season (P = 0.006). No significant difference was detected (P > 0.05) between seroprevalence in female and male cats and in cats from urban and suburban districts of Qatar. Despite the seasonal difference, the observed seroprevalence of T. gondii suggests high environmental contamination throughout the year, with some female cats generating more intense responses compared to males. Both findings merit further investigations.

Chronic Toxoplasma gondii in Nurr1-null heterozygous mice exacerbates elevated open field activity.

Science.gov (United States)

Eells, Jeffrey B; Varela-Stokes, Andrea; Guo-Ross, Shirley X; Kummari, Evangel; Smith, Holly M; Cox, Erin; Lindsay, David S

2015-01-01

Latent infection with Toxoplasma gondii is common in humans (approximately 30% of the global population) and is a significant risk factor for schizophrenia. Since prevalence of T. gondii infection is far greater than prevalence of schizophrenia (0.5-1%), genetic risk factors are likely also necessary to contribute to schizophrenia. To test this concept in an animal model, Nurr1-null heterozygous (+/-) mice and wild-type (+/+) mice were evaluate using an emergence test, activity in an open field and with a novel object, response to bobcat urine and prepulse inhibition of the acoustic startle response (PPI) prior to and 6 weeks after infection with T. gondii. In the emergence test, T. gondii infection significantly decreased the amount of time spent in the cylinder. Toxoplasma gondii infection significantly elevated open field activity in both +/+ and +/- mice but this increase was significantly exacerbated in +/- mice. T. gondii infection reduced PPI in male +/- mice but this was not statistically significant. Aversion to bobcat urine was abolished by T. gondii infection in +/+ mice. In female +/- mice, aversion to bobcat urine remained after T. gondii infection while the male +/- mice showed no aversion to bobcat urine. Antibody titers of infected mice were a critical variable associated with changes in open field activity, such that an inverted U shaped relationship existed between antibody titers and the percent change in open field activity with a significant increase in activity at low and medium antibody titers but no effect at high antibody titers. These data demonstrate that the Nurr1 +/- genotype predisposes mice to T. gondii-induced alterations in behaviors that involve dopamine neurotransmission and are associated with symptoms of schizophrenia. We propose that these alterations in murine behavior were due to further exacerbation of the altered dopamine neurotransmission in Nurr1 +/- mice.

Chronic Toxoplasma gondii in Nurr1-null heterozygous mice exacerbates elevated open field activity.

Directory of Open Access Journals (Sweden)

Jeffrey B Eells

Full Text Available Latent infection with Toxoplasma gondii is common in humans (approximately 30% of the global population and is a significant risk factor for schizophrenia. Since prevalence of T. gondii infection is far greater than prevalence of schizophrenia (0.5-1%, genetic risk factors are likely also necessary to contribute to schizophrenia. To test this concept in an animal model, Nurr1-null heterozygous (+/- mice and wild-type (+/+ mice were evaluate using an emergence test, activity in an open field and with a novel object, response to bobcat urine and prepulse inhibition of the acoustic startle response (PPI prior to and 6 weeks after infection with T. gondii. In the emergence test, T. gondii infection significantly decreased the amount of time spent in the cylinder. Toxoplasma gondii infection significantly elevated open field activity in both +/+ and +/- mice but this increase was significantly exacerbated in +/- mice. T. gondii infection reduced PPI in male +/- mice but this was not statistically significant. Aversion to bobcat urine was abolished by T. gondii infection in +/+ mice. In female +/- mice, aversion to bobcat urine remained after T. gondii infection while the male +/- mice showed no aversion to bobcat urine. Antibody titers of infected mice were a critical variable associated with changes in open field activity, such that an inverted U shaped relationship existed between antibody titers and the percent change in open field activity with a significant increase in activity at low and medium antibody titers but no effect at high antibody titers. These data demonstrate that the Nurr1 +/- genotype predisposes mice to T. gondii-induced alterations in behaviors that involve dopamine neurotransmission and are associated with symptoms of schizophrenia. We propose that these alterations in murine behavior were due to further exacerbation of the altered dopamine neurotransmission in Nurr1 +/- mice.

Epidemiological aspects of Toxoplasma gondii infection in riverside communities in the Southern Brazilian Amazon

Directory of Open Access Journals (Sweden)

Sérgio Neto Vitaliano

2015-06-01

Full Text Available INTRODUCTION: Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. M METHODS: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA kit. The hearts and brains of 50 chickens, which were raised free-range in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3. RESULTS: The overall seroprevalence of T. gondii was 56.7% (131/231. IgG antibodies were presented by 117 (89.3% and IgM by 14 (10.7% of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05; however, the comparison between localities showed that the seroprevalence of T. gondii was significantly lower among the individuals living in the Boca do Ituxi (p < 0.05 community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. CONCLUSIONS: These results support previous findings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.

First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana from Yucatan, Mexico

Directory of Open Access Journals (Sweden)

M. Torres-Castro

2016-03-01

Full Text Available Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13 in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico.

Detection of infection with toxoplasma Gondii in manatees (Trichechus inunguis) of the peruvian amazon

International Nuclear Information System (INIS)

Mathews Delgado, Patrick; Sanchez Perea, Nofre; Mathews Delgado, John Paul; Biffi Garcia, Claudia; Malheiros, Antonio Francisco; Garcia Davila, Carmen Rosa

2013-01-01

The Amazonian manatee (trichechus inunguis) is an aquatic mammal that inhabits freshwater environments and is endemic to the amazon basin. The presence of Toxoplasma gondii antibodies was investigated in 19 manatees in one rescue unit in the northern region of Peru. Antibodies to T. gondii were detected in 12 (63.2 %) of 19 animals by using the modified agglutination test (titer, 1:25), and no association between sex and age of the animals and the presence of T. gondii antibodies was observed (p < 0.05). the results suggest a contamination by T. gondii oocysts in the aquatic environment where these animals live.

Toxoplasma gondii abortion storm in sheep on a Texas farm and isolation of mouse virulent atypical genotype T. gondii from an aborted lamb from a chronically infected ewe

Science.gov (United States)

Sheep are commonly infected with the protozoan parasite, Toxoplasma gondii. Infection may cause early embryonic death and resorption, fetal death and mummification, abortion, stillbirth, and neonatal death. Most sheep acquire T. gondii infection after birth. Recent studies reported that repeat ovine...

Toxoplasma gondii Infection in Seagull Chicks Is Related to the Consumption of Freshwater Food Resources

Science.gov (United States)

Cabezón, Oscar; Cerdà-Cuéllar, Marta; Morera, Virginia; García-Bocanegra, Ignacio; González-Solís, Jacob; Napp, Sebastian; Ribas, Maria P.; Blanch-Lázaro, Berta; Fernández-Aguilar, Xavier; Antilles, Noelia; López-Soria, Sergio; Lorca-Oró, Cristina; Dubey, Jitender P.; Almería, Sonia

2016-01-01

Understanding the spread of Toxoplasma gondii (T. gondii) in wild birds, particularly in those with opportunistic feeding behavior, is of interest for elucidating the epidemiological involvement of these birds in the maintenance and dissemination of the parasite. Overall, from 2009 to 2011, we collected sera from 525 seagull chicks (Yellow-legged gull (Larus michahellis) and Audouin’s gull (L. audouinii)) from 6 breeding colonies in Spain and tested them using the modified agglutination test (MAT) for the presence of antibodies against T. gondii. Chick age was estimated from bill length. Main food source of seagull chicks was evaluated using stable isotope analyses from growing scapular feathers. Overall T. gondii seroprevalence was 21.0% (IC95% 17.5–24.4). A generalized linear mixed-effects model indicated that year (2009) and food source (freshwater) were risk factors associated to the individual risk of infection by T. gondii, while age (days) was close to significance. Freshwater food origin was related to the highest seroprevalence levels, followed by marine origin, supporting freshwater and sewages as important routes of dispersion of T. gondii. Year differences could indicate fluctuating rates of exposure of seagull chicks to T. gondii. Age ranged from 4 to 30 days and seropositivity tended to increase with age (P = 0.07), supporting that seropositivity is related to T. gondii infection rather than to maternal transfer of antibodies, which in gulls is known to sharply decrease with chick age. This study is the first to report T. gondii antibodies in Yellow-legged and Audouin’s gulls, thereby extending the range of intermediate hosts for this parasite and underscoring the complexity of its epidemiology. PMID:26974667

Dual Sarcocystis neurona and Toxoplasma gondii infection in a northern sea otter from Washington state, USA

Science.gov (United States)

Lindsay, D.S.; Thomas, N.J.; Rosypal, A.C.; Dubey, J.P.

2001-01-01

Dual Sarcocystis neurona and Toxoplasma gondii infection was observed in a Northern sea otter from Washington, USA. The animal was found stranded, convulsed, and died shortly thereafter. Encephalitis caused by both S. neurona and T. gondii was demonstrated in histological sections of brain. Immunohistochemical examination of sections with S. neurona specific antisera demonstrated developmental stages that divided by endopolygeny and produced numerous merozoites. PCR of brain tissue from the sea otter using primer pairs JNB33/JNB54 resulted in amplification of a 1100 bp product. This PCR product was cut in to 884 and 216 bp products by Dra I but was not cut by Hinf I indicating that it was S. neurona [J. Parasitol. 85 (1999) 221]. No PCR product was detected in the brain of a sea otter which had no lesions of encephalitis. Examination of brain sections using T. gondii specific antisera demonstrated tachyzoites and tissue cysts of T. gondii. The lesions induced by T. gondii suggested that the sea otter was suffering from reactivated toxoplasmosis. T. gondii was isolated in mice inoculated with brain tissue. A cat that was fed infected mouse brain tissue excreted T. gondii oocysts which were infective for mice. This is apparently the first report of dual S. neurona and T. gondii in a marine mammal.

Toxoplasma gondii seroprevalence and association with equine protozoal myeloencephalitis: A case-control study of Californian horses.

Science.gov (United States)

James, K E; Smith, W A; Packham, A E; Conrad, P A; Pusterla, N

2017-06-01

While toxoplasmosis is not commonly considered a clinical disease of equines, previous seroprevalence studies have reported differing background rates of Toxoplasma gondii infection in horses globally. The objective of this study was to evaluate possible associations between T. gondii seroprevalence and clinical signs of equine protozoal myeloencephalitis (EPM) in horses. Using a case-control study design, 720 Californian horses with neurologic signs compatible with EPM were compared to healthy, non-neurologic horses for the presence of T. gondii antibodies (using indirect fluorescent antibody tests [IFAT]). Toxoplasma gondii seroprevalence among cases and controls was determined at standard serum cut-offs: 40, 80, 160, 320, and 640. At a T. gondii titre cut-off of 320, horses with clinical signs compatible with EPM had 3.55 times the odds of a seropositive test compared to those without clinical signs (Pequines. Serologic testing of cerebrospinal fluid and isolation of T. gondii in EPM suspect cases should be considered. Future studies investigating the relationship between T. gondii and EPM are warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Toxoplasmosis and Polygenic Disease Susceptibility Genes: Extensive Toxoplasma gondii Host/Pathogen Interactome Enrichment in Nine Psychiatric or Neurological Disorders

Directory of Open Access Journals (Sweden)

C. J. Carter

2013-01-01

Full Text Available Toxoplasma gondii is not only implicated in schizophrenia and related disorders, but also in Alzheimer's or Parkinson's disease, cancer, cardiac myopathies, and autoimmune disorders. During its life cycle, the pathogen interacts with ~3000 host genes or proteins. Susceptibility genes for multiple sclerosis, Alzheimer's disease, schizophrenia, bipolar disorder, depression, childhood obesity, Parkinson's disease, attention deficit hyperactivity disorder (multiple sclerosis, and autism (, but not anorexia or chronic fatigue are highly enriched in the human arm of this interactome and 18 (ADHD to 33% (MS of the susceptibility genes relate to it. The signalling pathways involved in the susceptibility gene/interactome overlaps are relatively specific and relevant to each disease suggesting a means whereby susceptibility genes could orient the attentions of a single pathogen towards disruption of the specific pathways that together contribute (positively or negatively to the endophenotypes of different diseases. Conditional protein knockdown, orchestrated by T. gondii proteins or antibodies binding to those of the host (pathogen derived autoimmunity and metabolite exchange, may contribute to this disruption. Susceptibility genes may thus be related to the causes and influencers of disease, rather than (and as well as to the disease itself.

SAG2 locus genotyping of Toxoplasma gondii in meat products of ...

African Journals Online (AJOL)

Toxoplasmosis is an infection caused by Toxoplasma gondii, an intracellular obligate parasite. Its transmission is usually attributed to ingestion of undercooked or raw meat. The aim of this study was the detection and genotyping of T. gondii in meat products using the molecular method in East Azerbaijan. DNA was ...

Toxoplasma gondii 70 kDa heat shock protein: systemic detection is associated with the death of the parasites by the immune response and its increased expression in the brain is associated with parasite replication.

Directory of Open Access Journals (Sweden)

Paulo Victor Czarnewski Barenco

Full Text Available The heat shock protein of Toxoplasma gondii (TgHSP70 is a parasite virulence factor that is expressed during T. gondii stage conversion. To verify the effect of dexamethasone (DXM-induced infection reactivation in the TgHSP70-specific humoral immune response and the presence of the protein in the mouse brain, we produced recombinant TgHSP70 and anti-TgHSP70 IgY antibodies to detect the protein, the specific antibody and levels of immune complexes (ICs systemically, as well as the protein in the brain of resistant (BALB/c and susceptible (C57BL/6 mice. It was observed higher TgHSP70-specific antibody titers in serum samples of BALB/c compared with C57BL/6 mice. However, the susceptible mice presented the highest levels of TgHSP70 systemically and no detection of specific ICs. The DXM treatment induced increased parasitism and lower inflammatory changes in the brain of C57BL/6, but did not interfere with the cerebral parasitism in BALB/c mice. Additionally, DXM treatment decreased the serological TgHSP70 concentration in both mouse lineages. C57BL/6 mice presented high expression of TgHSP70 in the brain with the progression of infection and under DXM treatment. Taken together, these data indicate that the TgHSP70 release into the bloodstream depends on the death of the parasites mediated by the host immune response, whereas the increased TgHSP70 expression in the brain depends on the multiplication rate of the parasite.

Stillbirth history and Toxoplasma gondii infection in women attending public health centers in a northern Mexican City

Science.gov (United States)

Alvarado-Esquivel, C.; Pacheco-Vega, S. J.; Salcedo-Jaquez, M.; Sánchez-Anguiano, L. F.; Hernández-Tinoco, J.; Rábago-Sánchez, E.; Centeno-Tinoco, M. M.; Flores-Garcia, I. D.; Ramos-Nevarez, A.; Cerrillo-Soto, S. M.; Guido-Arreola, C. A.; Beristain-García, I.; Liesenfeld, O.; Berumen-Segovia, L. O.; Saenz-Soto, L.; Sifuentes-Álvarez, A.

2015-01-01

Through a cross-sectional study design, 150 women attending public health centers with a history of stillbirths were examined for anti-Toxoplasma gondii IgG and IgM antibodies in Durango City, Mexico. Bivariate and multivariate analyses were used to assess the association of T. gondii seropositivity with the characteristics of the women with stillbirth history. Of the 150 women (mean age: 32.09 ± 9.16 years) studied, 14 (9.3%) had anti-T. gondii IgG antibodies and six (42.9%) of them were also positive for anti-T. gondii IgM antibodies. Multivariate analysis showed that T. gondii seropositivity was associated with high frequency (4–7 days a week) of eating meat (OR = 5.52; 95% CI: 1.48–20.59; P = 0.01), history of lymphadenopathy (OR = 4.52; 95% CI: 1.14–17.82; P = 0.03), and history of surgery (OR = 8.68; 95% CI: 1.04–72.15; P = 0.04). This is the first study on the seroepidemiology of T. gondii infection in women with a history of stillbirths in Mexico. The association of T. gondii exposure with a history of surgery warrants for further research. Risk factors for T. gondii infection found in the present survey may help to design optimal educational programs to avoid T. gondii infection. PMID:26185685

Prevalence of Toxoplasma gondii antibodies in domestic donkeys (Equus asinus) in Durango, Mexico slaughtered for human consumption.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Alvarado-Esquivel, Domingo; Dubey, Jitender P

2015-01-17

Nothing is known about Toxoplasma gondii prevalence in donkeys in Mexico. Meat from donkey is consumed by humans in Mexico and also exported to other countries. We sought to determine the presence of antibodies against T. gondii in 239 domestic donkeys (Equus asinus) for slaughter in Durango, Mexico using the modified agglutination test (MAT). Donkeys were sampled in four premises (trade centers) where donkeys were gather for shipment to abattoirs in other Mexican states. Antibodies to T. gondii were found in 26 (10.9%) of 239 donkeys, with MAT titers of 1:25 in 7, 1:50 in 11, 1:100 in 6, and 1:200 in 2. Seropositive donkeys were found in three (75%) of the four gathering premises studied. Seroprevalence in donkeys varied from 0% to 23.1% among gathering premises. The seroprevalence of T. gondii infection was comparable among donkeys regardless their age, sex or health status. Seropositivity to T. gondii was found in donkeys between 1 to 12 years old. Multivariate analysis showed that seropositivity to T. gondii was associated with the gathering premises (OR = 1.58; 95% CI: 1.11-2.24; P = 0.009). This is the first report of T. gondii infection in donkeys in Mexico. Results indicate that consumption of undercooked or raw meat from T. gondii-infected donkeys is potentially a source of T. gondii infection for humans.

Seroprevalensi Toxoplasma gondii pada Kambing dan Bioassay Patogenitasnya pada Kucing

Directory of Open Access Journals (Sweden)

Ni Made Yunik Novita Dewi Dewi

2013-11-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE The study aimed to determine seroprevalence of Toxoplasmosis in goats sloughtered at Kampung Jawa, Denpasar, Bali and to evaluate their pathogenicities through bioassay in cats.One hundred serums and meats of goats were collected. Anti-Toxoplasma gondii antibody was determined using Indirect Haemaglutination (IHA test. The pathogenicity bioassay of Toxoplasma gondii was carried out through inoculating the meats of goats which had seropositive of Toxoplasma gondii to the cats. The pathogenicity was evaluated using the intensity of oocyte sheding from the cats. The result showed that the seroprevalence of Toxoplasmosis was 46%. There was not significant difference between pathogenicity of Toxoplasma gondii in cat inoculated with meat of goat which had a high and low titer of antibody against Toxoplasma gondii. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; text-align:justify; line-height:150%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

Lack of Serological and Molecular Association between Toxoplasma Gondii Exposure and Obesity: A Case-Control Study

Science.gov (United States)

Alvarado-Esquivel, Cosme; Maldonado-Soto, Edith; Sanchez-Anguiano, Luis Francisco; Hernandez-Tinoco, Jesus; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Sandoval-Carrilo, Ada Agustina; Salas-Pacheco, Jose Manuel; Antuna-Salcido, Elizabeth Irasema; Estrada-Martinez, Sergio; Guido-Arreola, Carlos Alberto

2017-01-01

The association between T. gondii infection and obesity has been scantly studied. Through an age-, and gender-matched case-control study, we determined the association of T. gondii infection and obesity using serological and molecular methods. Cases included 203 persons with obesity, and controls included 203 persons without obesity. Participants were tested for the presence of anti-Toxoplasma IgG antibodies using an enzyme-linked immunoassay (EIA). IgG seropositive individuals were further tested for the presence of anti-T. gondii IgM antibodies using an EIA, and T. gondii DNA by polymerase chain reaction (PCR). Anti-T. gondii IgG antibodies were found in 16 (7.9%) of the 203 cases and in 18 (8.9%) of the 203 controls (OR=0.87; 95% CI: 0.43-1.77; P=0.72). One (6.3%) of the 16 anti-T. gondii IgG seropositive cases and 6 (33.3%) of the 18 anti-T. gondii IgG seropositive controls were positive for IgM (P=0.09). Mean body mass index (35.5 ± 4.5) in T. gondii seropositive cases was similar (P=0.57) to that (36.1 ± 4.5) found in T. gondii seronegative cases. Stratification by obesity classes (I, II, and III) did not reveal differences (P>0.05) in seroprevalences (7.8%, 7.9%, and 8.1%, respectively) or high (>150 IU/ml) IgG antibody levels (3.3%, 3.9%, and 2.7%, respectively). PCR was positive in 5 (31.3%) of 16 cases, and in 5 (27.8%) of 18 controls examined (P=1.0). We found no serological or molecular evidence of an association between T. gondii infection and obesity in people attending a public health center in the northern Mexican city of Durango. PMID:28824343

Toxoplasma gondii: infection natural congenital in cattle and an experimental inoculation of gestating cows with oocysts.

Science.gov (United States)

Costa, Gustavo Henrique Nogueira; da Costa, Alvimar José; Lopes, Welber Daniel Zanetti; Bresciani, Katia Denise Saraiva; dos Santos, Thais Rabelo; Esper, César Roberto; Santana, Aureo Evangelista

2011-01-01

Two studies, of a natural infection and an experimental infection, were performed in order to study congenital transmission of Toxoplasma gondii in cattle. In the first study, 50 fetuses were harvested from gestating cows that were eutanasied at a municipal slaughterhouse in Jaboticabal, São Paulo state, Brazil. In the second study, 11 gestating cows were divided into four groups for inoculation with T. gondii: GI consisted of three cows inoculated with 1.0 × 10(5) oocysts during their first trimester of gestation; GII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their second trimester of gestation; GIII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their last trimester of gestation; and GIV consisted of two control cows, one during its first and the other during its second trimester of gestation. In both studies, the presence of T. gondii was confirmed both indirectly by immunofluorescence assay (IFAT). In the natural infection experiment, 18% (9/50) of the gestating cows were confirmed to have specific antibodies (IFAT--1:64) against T. gondii. The bioassay was able to diagnose the presence of T. gondii in the tissue samples from three calves. In the second experiment, the nine cows from groups I, II and III presented with specific antibodies (IFAT) against T. gondii. In contrast, T. gondii could not be detected by IFAT, histopathological examination or the bioassay in any of the nine calves born to cows experimentally infected with T. gondii oocysts. Based on the results from both studies, we conclude that congenital infection of T. gondii in cattle, while infrequent, does occur naturally. The pathogenicity of the strain of T. gondii may influence the likelihood of this route of transmission. Copyright © 2010 Elsevier Inc. All rights reserved.

Reciprocal moderation by Toxoplasma gondii seropositivity and blood phenylalanine - tyrosine ratio of their associations with trait aggression.

Science.gov (United States)

Mathai, Ashwin Jacob; Lowry, Christopher A; Cook, Thomas B; Brenner, Lisa A; Brundin, Lena; Groer, Maureen W; Peng, Xiaoqing; Giegling, Ina; Hartmann, Annette M; Konte, Bettina; Friedl, Marion; Fuchs, Dietmar; Rujescu, Dan; Postolache, Teodor T

2016-12-01

We previously reported that trait aggression, proposed as an endophenotype for suicidal behavior, is positively associated with Toxoplasma gondii ( T. gondii ) seropositivity in females, but not in males. Additionally, older males seropositive for T. gondii had lower scores on measures of trait aggression, including self-aggression. Trait aggression may be influenced by dopaminergic signaling, which is known to be moderated by gender and age, and potentially enhanced in T. gondii positives through the intrinsic production of dopamine by the microorganism. Therefore, we investigated associations between trait aggression and interactions between T. gondii enzyme-linked immunoabsorbant assay (ELISA) IgG titer-determined seropositivity and high-performance liquid chromatography- (HPLC-) measured blood levels of dopamine precursors phenylalanine (Phe), tyrosine (Tyr), and their ratio in a sample of 1000 psychiatrically healthy participants. Aggressive traits were assessed using the questionnaire for measuring factors of aggression (FAF), the German version of the Buss-Durkee hostility questionnaire. We found that 1) the decrease in trait aggression scores in T. gondii -positive older males was only present in individuals with a low Phe:Tyr ratio, and 2) that there was a positive correlation between Phe:Tyr ratio and total aggression and selected subscales of aggression in T. gondii -positive males, but not in T. gondii -negative males. These findings point toward a gender-specific reciprocal moderation by Phe:Tyr ratio and T. gondii seropositivity of their associations with aggression scores, and lead to experimental interventions geared to manipulating levels of dopamine precursors in selected T. gondii positive individuals with increased propensity for aggression.

Anti-Toxoplasma gondii antibodies in patients with beta-hemoglobinopathies: the first report in the Americas.

Science.gov (United States)

Ferreira, Marina Neves; Bonini-Domingos, Claudia Regina; Fonseca Estevão, Isabeth; de Castro Lobo, Clarice Lopes; Souza Carrocini, Gisele Cristina; Silveira-Carvalho, Aparecida Perpétuo; Ricci, Octávio; de Mattos, Luiz Carlos; Brandão de Mattos, Cinara Cássia

2017-06-14

In Brazil, there have been no previous studies of Toxoplasma gondii infection in sickle cell anemia patients and carriers of severe forms of beta-thalassemia. This study evaluated T. gondii infection in patients with beta-hemoglobinopathies. A total of 158 samples, 77 (48.7%) men and 81 (51.3%) women, were evaluated. Three groups were formed: G1 (85 patients with sickle cell disease); G2 (11 patients with homozygous beta-thalassemia; G3 (62 patients with heterozygous beta-thalassemia). ELISA was employed to identify anti-T. gondii IgM and IgG antibodies, and molecular analysis was performed to determine beta-hemoglobin mutations. Fisher's exact test was used to compare frequencies of anti-T. gondii IgM and IgG antibodies in respect to gender and age. Anti-T. gondii IgG antibodies were found in 43.5% of individuals in G1, 18.1% in G2 and 50% in G3. All samples from G1 and G2 were seronegative for anti-T. gondii IgM antibodies, but 3.2% from G3 were seropositive. Considering anti-T. gondii IgG antibodies, no statistical significant differences were found between these groups nor in seroprevalence between genders within each group. Despite this, comparisons of the mean ages between G1, G2 and G3 were statistically significant (G2 vs. G1: p value = 0.0001; G3 vs. G1: p-value <0.0001; G3 vs. G2: p-value = 0.0001). A comparison by age of patients with sickle cell anemia showed a trend of lower risk of infection among younger individuals. Therefore, this study demonstrates that T. gondii infection occurs in patients with beta-thalassemia and sickle cell anemia in Brazil as seen by the presence of anti-T. gondii IgM and IgG antibodies.

Detection and genotyping of Toxoplasma gondii DNA in the blood and milk of naturally infected donkeys (Equus asinus).

Science.gov (United States)

Mancianti, Francesca; Nardoni, Simona; Papini, Roberto; Mugnaini, Linda; Martini, Mina; Altomonte, Iolanda; Salari, Federica; D'Ascenzi, Carlo; Dubey, Jitender P

2014-04-03

Toxoplasma gondii is a worldwide zoonotic protozoan. Consumption of raw milk from infected animals is considered a risk factor for acquiring toxoplasmosis in humans. Recently, donkey milk has been indicated for therapeutic and nutritional purposes and T. gondii infection is common in donkeys. The purpose of the present paper was to detect the presence of parasite DNA in milk of T. gondii positive donkeys. Antibodies to T. gondii were found in 11 out of 44 healthy lactating donkeys by IFAT. T. gondii DNA was detected by PCR in blood of 6 and milk of 3 seropositive jennies. Results of limited RFLP-PCR genotyping indicated the presence of T. gondii genotype II or III, commonly found in Europe. The occurrence of T. gondii DNA in milk suggests that the consumption of raw milk from seropositive donkeys could be a potential source of human infection.

Mouse-virulent Toxoplasma gondii isolated from feral cats on Mona Island, Puerto Rico.

Science.gov (United States)

Dubey, J P; López-Torres, H Y; Sundar, N; Velmurugan, G V; Ajzenberg, D; Kwok, O C H; Hill, R; Dardé, M L; Su, C

2007-12-01

Cats are essential in the life cycle of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts. Samples of serum, feces, and tissues from cats from Mona, a remote island off the coast of Puerto Rico, were examined for T. gondii infection. Antibodies to T. gondii were assayed by the modified agglutination test and found in 16 of 19 (84.2%) of cats, with titers of 1:10 in 2, 1:80 in 1, 1:160 in 4, 1:320 in 3, and 1:1,280 or higher in 6. Tissues of 19 of the 20 cats were bioassayed in mice for T. gondii infection. Toxoplasma gondii was isolated from tissues of 12 cats: from the hearts of 9, skeletal muscle of 10, and brain of 1 cat. All infected mice from 10 of 12 isolates died of acute toxoplasmosis during primary infection. Genotyping of these 12 T. gondii isolates (designated (TgCatPr 1-12) by 10 multilocus PCR-RFLP markers, i.e., SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico, and the 6 multilocus microsatellite markers TUB2, W35, TgM-A, B18, B17, and M33, revealed 7 genotypes; 5 isolates had Type I alleles at all loci except at 1 microsatellite locus, and the remainder were atypical. The latter isolates of T. gondii were different biologically and phenotypically from the feline isolates from the rest of the Americas. One isolate (TgCatPr 12) was a mixed infection with 2 genotypes.

Seroepidemiology of Toxoplasma gondii in dogs in the State of Rio de Janeiro

Directory of Open Access Journals (Sweden)

Nathalie Costa da Cunha

2016-11-01

Full Text Available ABSTRACT. Cunha N.C., Cordeiro M.D., Bravo S.A.C., Matos P.C.M., Almosny N.R.P. & da Fonseca A.H. [Seroepidemiology of Toxoplasma gondii in dogs in the State of Rio de Janeiro.] Soroepidemiologia de Toxoplasma gondii em cães no estado do Rio de Janeiro. Revista Brasileira de Medicina Veterinária 38(supl. 3: 114-121, 2016. Departamento de Saúde Coletiva Veterinária e Saúde Pública, Faculdade de Veterinária. Universidade Federal Fluminense, Vital Brazil, Niterói, RJ, Brazil. E-mail: nathaliecunha@id.uff.br Toxoplasmosis is a serious public health problem worldwide as it can cause prenatal and neonatal morbidity and mortality in humans. Although dogs are not definitive hosts of T. gondii, they play an important role in the mechanical dissemination of oocysts. This study aimed to carry out a seroepidemiological investigation of anti-Toxoplasma gondii antibodies in domestic dogs from seven municipalities in the state of Rio de Janeiro, Brazil. A crosssectional epidemiological study was carried out to evaluate the profile of anti-Toxoplasma gondii IgG antibodies in dogs from canine sera from different municipalities in the state of Rio de Janeiro. The municipalities studied were Cachoeiras de Macacu, Guapimirim, Itaboraí, Magé, Resende, Seropédica and Silva Jardim. The detection of antibodies of the IgG class anti-Toxoplasma gondii was performed using the indirect enzyme immunoadsorption (ELISA assay and the statistical analyzes used were the chi-square test and the prevalence ratio. Of the 651 samples tested, 300 were reactive for T. gondii, representing a relative frequency of 46.08% of seroreactive dogs. It was concluded that dogs are good sentinels for evaluations of risk for occurrence of T. gondii, emphasizing those coming from rural areas and that there was no difference in the occurrence of serorreative dogs in front of different municipalities studies of the state of Rio de Janeiro.

Seroprevalence of Toxoplasma gondii in wild boars, red deer and roe deer in Poland

Directory of Open Access Journals (Sweden)

Witkowski Lucjan

2015-01-01

Full Text Available Little is known about the prevalence of Toxoplasma gondii in wild life, particularly game animals in Poland. Meat juice collected during the 2009/2010 and 2010/2011 hunting seasons from 552 red deer (Cervus elaphus, 367 wild boars (Sus scrofa and 92 roe deer (Capreolus capreolus was tested for T. gondii antibodies using the multi-species ID Screen Toxoplasmosis Indirect kit (IDvet, Montpellier, France. Antibodies to T. gondii were detected in 24.1% of red deer (95% CI: 20.7%, 27.8%, 37.6% of wild boar (95% CI: 32.8%, 42.7% and 30.4% of roe deer (95% CI: 22.0%, 40.5%. To the authors’ best knowledge, this is the first epidemiological report of T. gondii prevalence in red deer, roe deer and wild boars in Poland. T. gondii is present in wildlife animal tissues and consumption of the game may be a potential source of infection for humans.

Toxoplasma gondii exposes phosphatidylserine inducing a TGF-β1 autocrine effect orchestrating macrophage evasion

International Nuclear Information System (INIS)

Seabra, Sergio H.; Souza, Wanderley de; Matta, Renato A. da

2004-01-01

Toxoplasmosis is a worldwide disease caused by Toxoplasma gondii. Activated macrophages control T. gondii growth by nitric oxide (NO) production. However, T. gondii active invasion inhibits NO production, allowing parasite persistence. Here we show that the mechanism used by T. gondii to inhibit NO production persisting in activated macrophages depends on phosphatidylserine (PS) exposure. Masking PS with annexin-V on parasites or activated macrophages abolished NO production inhibition and parasite persistence. NO production inhibition depended on a transforming growth factor-β 1 (TGF-β 1 ) autocrine effect confirmed by the expression of Smad 2 and 3 in infected macrophages. TGF-β 1 led to inducible nitric oxide synthase (iNOS) degradation, actin filament (F-actin) depolymerization, and lack of nuclear factor-κB (NF-κB) in the nucleus. All these features were reverted by TGF-β 1 neutralizing antibody treatment. Thus, T. gondii mimics the evasion mechanism used by Leishmania amazonensis and also the anti-inflammatory response evoked by apoptotic cells

Epidemiology and pathology of Toxoplasma gondii in free-ranging California sea lions (Zalophus californianus)

OpenAIRE

Carlson-Bremer, D; Colegrove, KM; Gulland, FMD; Conrad, PA; Mazet, JAK; Johnson, CK

2015-01-01

© Wildlife Disease Association 2015. The coccidian parasite Toxoplasma gondii infects humans and warm-blooded animals worldwide. The ecology of this parasite in marine systems is poorly understood, although many marine mammals are infected and susceptible to clinical toxoplasmosis. We summarized the lesions associated with T. gondii infection in the California sea lion (Zalophus californianus) population and investigated the prevalence of and risk factors associated with T. gondii exposure, a...

Epidemiology and pathology of Toxoplasma gondii in free-ranging California sea lions (Zalophus californianus).

Science.gov (United States)

Carlson-Bremer, Daphne; Colegrove, Kathleen M; Gulland, Frances M D; Conrad, Patricia A; Mazet, Jonna A K; Johnson, Christine K

2015-04-01

The coccidian parasite Toxoplasma gondii infects humans and warm-blooded animals worldwide. The ecology of this parasite in marine systems is poorly understood, although many marine mammals are infected and susceptible to clinical toxoplasmosis. We summarized the lesions associated with T. gondii infection in the California sea lion (Zalophus californianus) population and investigated the prevalence of and risk factors associated with T. gondii exposure, as indicated by antibody. Five confirmed and four suspected cases of T. gondii infection were identified by analysis of 1,152 medical records of necropsied sea lions from 1975-2009. One suspected and two confirmed cases were identified in aborted fetuses from a sea lion rookery. Toxoplasmosis was the primary cause of death in five cases, including the two fetuses. Gross and histopathologic findings in T. gondii-infected sea lions were similar to those reported in other marine mammals. The most common lesions were encephalitis, meningitis, and myocarditis. The antibody prevalence in stranded, free-ranging sea lions for 1998-2009 was 2.5% (±0.03%; IgG titer 640). There was an increase in odds of exposure in sea lions with increasing age, suggesting cumulative risk of exposure and persistent antibody over time. The occurrence of disseminated T. gondii infection in aborted fetuses confirms vertical transmission in sea lions, and the increasing odds of exposure with age is consistent with additional opportunities for horizontal transmission in free-ranging sea lions over time. These data suggest that T. gondii may have two modes of transmission in the sea lion population. Overall, clinical disease was uncommon in our study which, along with low prevalence of T. gondii antibody, suggests substantially less-frequent exposure and lower susceptibility to clinical disease in California sea lions as compared to sympatric southern sea otters (Enhydra lutris nereis).

Seroprevalence of Toxoplasma gondii from free-ranging black bears ( Ursus americanus ) from Florida.

Science.gov (United States)

Chambers, D L; Ulrey, W A; Guthrie, J M; Kwok, O C H; Cox, J J; Maehr, D S; Dubey, J P

2012-06-01

Toxoplasma gondii is a significant worldwide parasitic protozoan. In the present study, prevalence of antibodies of T. gondii was examined from 29 free-ranging black bears ( Ursus americanus ) from south-central Florida where the host species was listed as state threatened during this project. Overall T. gondii prevalence was found to be 44.8%, specifically 46.2% in male and 43.8% in female U. americanus , using a modified agglutination test (1:25 titer). Seroprevalence differences between sexes were not significant (P > 0.05). Results of the present study add supportive data to the growing body of evidence suggesting that U. americanus has one of the highest T. gondii seroprevalences among all known intermediate hosts. In addition, our data emphasize the importance of understanding parasitic disease dynamics from a conservation perspective.

Detection of Toxoplasma gondii oocysts in soils in northwestern China using a new semi-nested PCR assay.

Science.gov (United States)

Wang, Meng; Meng, Peng; Ye, Qiang; Pu, Yuan-Hua; Yang, Xiao-Yu; Luo, Jian-Xun; Zhang, Nian-Zhang; Zhang, De-Lin

2014-09-28

Toxoplasma gondii is a zoonotic pathogen that can infect a range of animals and humans. Ingestion of T. gondii oocysts in soil is a significant transmission route for humans and animals acquiring toxoplasmosis. In the present study, we developed a new semi-nested PCR method to determine T. gondii oocysts distribution in soils in northwestern China. The one tube semi-nested PCR assay was developed to detect the oocysts of T. gondii in soil, targeting the repetitive 529 bp fragment of T. gondii genomic DNA. Then a total of 268 soil samples, including 148 samples from Gansu Province and 120 samples from Qinghai Province, northwestern China, were examined by the semi-nested PCR method. One third of the positive samples were sequenced. The sensitivity of the semi-nested PCR assay was 10(2)  T. gondii oocysts in 5 g soil sample. Investigation of soil samples from northwestern China showed that 34 out of 268 soil samples (12.69%) were T. gondii positive. Sequences of the partial 529 bp fragments varied from 0-1.2% among the sequenced samples. The prevalence of T. gondii oocysts in soil from cities (24/163) was slightly higher than that in soils from pasturing areas (10/105) (P = 0.21). Among the different regions in cities, the prevalence of T. gondii oocysts in soils from parks was 14.15%, whereas that in soils from schools was 19.05%. The present study firstly reported the prevalence of T. gondii oocysts in soils in northwest China using a novel semi-nested PCR assay, which provided baseline data for the effective prevention and control of toxoplasmosis in this region.

Toxoplasma gondii peptide ligands open the gate of the HLA class I binding groove

DEFF Research Database (Denmark)

McMurtrey, Curtis; Trolle, Thomas; Sansom, Tiffany

2016-01-01

HLA class I presentation of pathogen-derived peptide ligands is essential for CD8+ T cell recognition of Toxoplasma gondii infected cells. Currently, little data exist pertaining to peptides that are presented after T. gondii infection. Herein we purify HLA-A*02:01 complexes from T. gondii infect...

Serotyping of Toxoplasma gondii in Cats (Felis domesticus) Reveals Predominance of Type II Infections in Germany

Science.gov (United States)

Background: Cats are definitive hosts of Toxoplasma gondii and play an essential role in the epidemiology of this parasite. The study aims at clarifying whether cats are able to develop specific antibodies against different clonal types of T. gondii and to determine by serotyping the T. gondii clona...

Toxoplasma gondii in small neotropical wild felids

Directory of Open Access Journals (Sweden)

William Alberto Cañon-Franco

2013-02-01

Full Text Available In the last decade, studies on wildlife worldwide have discovered key epidemiological aspects of the sylvatic cycle of Toxoplasma gondii. However, despite the known role of wild felines as definitive hosts in the transmission and maintenance of this parasite, few studies have focused on the involvement of these animals. Brazil exhibits the largest number of wild felid species in the Americas, all of which have a critical conservation status. However, serological detections, epidemiological studies and some molecular characterizations of T. gondii have primarily used Neotropical felid populations that are maintained in captivity, which does not reflect the disease behavior in free-living conditions. A systematic review of the worldwide scientific literature was conducted focusing on toxoplasmosis in small Neotropical felids. This review covered a number of aspects, including the state of scientific research, parasite transmission in the wild, the genetic characteristics of isolates, the relationship between these genetic characteristics and the pathogenicity of the parasite, and the risk factors linked to conflicts with humans. The present review shows the relevance of studying these felid populations based on their frequent interactions with humans in peri-urban areas and the need for further comprehensive studies to establish the real significance of T. gondii in public and animal health in tropical and temperate regions.

Molecular and serological prevalence of Toxoplasma gondii and Anaplasma spp. infection in goats from Chongqing Municipality, China

Directory of Open Access Journals (Sweden)

Zhou Zuoyong

2018-01-01

Full Text Available Toxoplasmosis and anaplasmosis are severe zoonotic diseases, the former caused by Toxoplasma gondii and the latter by Anaplasma spp. In the present study, 332 goat blood samples were randomly collected from Chongqing Municipality, China to screen for T. gondii and Anaplasma spp. We used a polymerase chain reaction (PCR to detect DNA, and enzyme-linked immunosorbent assay (ELISA to test for T. gondii antibodies. The prevalence of T. gondii and Anaplasma spp. was 38% and 35% respectively by PCR, and 42% for T. gondii antibodies by ELISA. The co-infection rate by T. gondii and Anaplasma was 13%, where the two predominant pathogens co-infecting were Anaplasma phagocytophilum + A. bovis (10%, followed by T. gondii + A. phagocytophilum (9.64%. While co-infection by three pathogens varied ranging from 1.81% to 5.72%, less than 1% of goats were found to be positive for four pathogens. This is the first investigation of T. gondii and Anaplasma spp. infection in goats from Chongqing.

Incidence of adult brain cancers is higher in countries where the protozoan parasite Toxoplasma gondii is common

Science.gov (United States)

Thomas, Frédéric; Lafferty, Kevin D.; Brodeur, Jacques; Elguero, Eric; Gauthier-Clerc, Michel; Missé, Dorothée

2012-01-01

We explored associations between the common protozoan parasite Toxoplasma gondii and brain cancers in human populations. We predicted that T. gondii could increase the risk of brain cancer because it is a long-lived parasite that encysts in the brain, where it provokes inflammation and inhibits apoptosis. We used a medical geography approach based on the national incidence of brain cancers and seroprevalence of T. gondii. We corrected reports of incidence for national gross domestic product because wealth probably increases the ability to detect cancer. We also included gender, cell phone use and latitude as variables in our initial models. Prevalence of T. gondii explained 19 per cent of the residual variance in brain cancer incidence after controlling for the positive effects of gross domestic product and latitude among nations. Infection with T. gondii was associated with a 1.8-fold increase in the risk of brain cancers across the range of T. gondii prevalence in our dataset (4–67%). These results, though correlational, suggest that T. gondii should be investigated further as a possible oncogenic pathogen of humans.

Detection of Toxoplasma gondii DNA in sera samples of mice experimentally infected

Directory of Open Access Journals (Sweden)

H. Langoni

2006-04-01

Full Text Available Detection of Toxoplasma gondii (T. gondii DNA in blood can help to diagnose the disease in its acute phase; however, it must be considered that hemoglobin, present in blood, can inhibit polymerase activity, making impracticable the detection of DNA in samples. Mice were experimentally infected via oral route with ME49 and BTU2 strains cysts and RH strain tachyzoites; polymerase chain reaction was used to detect T. gondii DNA in mice sera 18, 24, 48, 96, and 192 hours post infection (PI. Toxoplama gondii DNA was detected in only one animal infected with BTU2 strain, genotype III (isolated from a dog with neurological signs 18 hours PI. The agent's DNA was not detected in any sample of the other experimental groups. New studies must be carried out to verify the technique sensitivity in researches on this agent's genetic material using sera samples of acute-phase toxoplasmosis patients, especially in cases of immunosuppression.

Immunodiagnosis and molecular validation of Toxoplasma gondii-recombinant dense granular (GRA) 7 protein for the detection of toxoplasmosis in patients with cancer.

Science.gov (United States)

Arab-Mazar, Zahra; Fallahi, Shirzad; Koochaki, Ameneh; Haghighi, Ali; Seyyed Tabaei, Seyyed Javad

2016-02-01

Serological assays for the diagnosis of toxoplasmosis mostly rely on the tachyzoite specific antigens of Toxoplasma gondii, which are difficult to produce by conventional methods. The aim of this study was to clone and express of GRA7 protein of T. gondii and evaluate its potential for immunodiagnosis of toxoplasmosis in cancer patients. As well as validate the results using a new molecular assay, LAMP technique. The GRA7 gene was successfully cloned, expressed and purified by affinity chromatography and the production was evaluated by SDS PAGE, dot blot and western blot analyses. The rGRA7 was used for developing an ELISA based on the rGRA7 using sera from patients with toxoplasmosis and healthy controls. Furthermore, 50 serum samples from leukemic children infected with toxoplasmosis and 50 seronegative controls were included to evaluate the sensitivity and specificity of rGRA7 based ELISA. Finally, the LAMP technique was used to assess the accuracy and validity of the results obtained by rGRA7 based ELISA. The consistency of the results of two tests was determined by using the Kappa coefficient of agreement. The rGRA7 showed higher and optimum immunoreactivity with 1:100 dilution of serum from Toxoplasma infected patients. The sensitivity and specificity of test were calculated as 92 and 94%, respectively. According to the Kappa coefficient of agreement, there was a significant conformance between the results obtained by ELISA based on the rGRA7 and the results of LAMP technique (≈96%, Ptoxoplasmosis in patients including patients with cancer. Copyright © 2015. Published by Elsevier GmbH.

Role of NETs in the difference in host susceptibility to Toxoplasma gondii between sheep and cattle.

Science.gov (United States)

Yildiz, Kader; Gokpinar, Sami; Gazyagci, Aycan Nuriye; Babur, Cahit; Sursal, Neslihan; Azkur, Ahmet Kursat

2017-07-01

The main aim of this study was to compare extracellular traps (NETs) formation by polymorphonuclear neutrophils (PMNs) of cattle and sheep when exposed to T. gondii tachyzoites in vitro. The effects of parasite concentrations and different incubation periods on NETs development in cattle and sheep PMNs were studied. The effect of NET structures on host cell invasion by tachyzoites was also studied. This is the first report of NETs development by sheep and cattle PMNs against T. gondii in vitro. T. gondii-induced extracellular DNA production from PMNs was dependent on tachyzoite concentrations and incubation time in both sheep and cattle. Many nuclear and cytoplasmic changes were observed in sheep and cattle PMNs after exposure to T. gondii tachyzoites. The typical appearance of NETs, with MPO, NE and histone (H3) attached to extracellular DNA, was observed. Tachyzoites were entrapped within this structure. Myeloperoxidase (MPO) activity was higher in the cattle PMN-tachyzoite co-cultures than sheep. NETs structures released from sheep PMNs caused mechanical immobilisation of T. gondii tachyzoites, however, NET structures released from cattle PMNs may be lethal to tachyzoites. Bovine MPO may have a lethal effect on T. gondii tachyzoites in vitro during a 3h incubation. Besides other mechanisms that effect on host susceptibility to T. gondii in sheep and cattle, extracellular traps formation as a part of immunological reactions may be play a role in host susceptibility to T. gondii. Copyright © 2017 Elsevier B.V. All rights reserved.

Influence of Toxoplasma Gondii Infection on Symptoms and Signs of Premenstrual Syndrome: A Cross-sectional Study

Science.gov (United States)

Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Pérez-Álamos, Alma Rosa; Rico-Almochantaf, Yazmin del Rosario; Estrada-Martínez, Sergio; Vaquera-Enriquez, Raquel; Díaz-Herrera, Arturo; Ramos-Nevarez, Agar; Sandoval-Carrillo, Ada Agustina; Salas-Pacheco, José Manuel; Cerrillo-Soto, Sandra Margarita; Antuna-Salcido, Elizabeth Irasema; Liesenfeld, Oliver; Guido-Arreola, Carlos Alberto

2016-01-01

Infection with Toxoplasma gondii in brain may cause some symptoms that resemble those in women with premenstrual syndrome. To determine the association of T. gondii infection with symptoms and signs of premenstrual syndrome, we examined 489 women aged 30–40 years old. Sera of participants were analyzed for the presence of anti-Toxoplasma IgG and IgM antibodies using enzyme-linked immunoassays (EIA) and T. gondii DNA by polymerase chain reaction (PCR). Anti-T. gondii IgG antibodies were found in 38 (7.8%) of the women studied. Anti-T. gondii IgM antibodies were found in 13 (34.2%) of the 38 IgG seropositive women. Logistic regression showed two variables associated with seropositivity to T. gondii: presence of diarrhea (odds ratio [OR] = 6.10; 95% confidence interval [CI]: 1.37–27.85; P = 0.01) and weight gain (OR = 2.89; 95% CI: 1.37–6.07; P = 0.005), and two variables associated with high (>150 IU/ml) levels of IgG against T. gondii: presence of diarrhea (OR = 7.40; 95% CI: 1.79–30.46; P = 0.006) and abdominal inflammation (OR = 3.38; 95% CI: 1.13–10.10; P = 0.02). Positivity to EIA IgG and PCR was positively associated with obesity and negatively associated with joint pain by bivariate analysis. Our study for the first time reveals a potential association of T. gondii infection with clinical manifestations of premenstrual syndrome. PMID:27980858

Toxoplasma gondii in the Cornigliese sheep breed in Italy: Meat juice serology, in vitro isolation and genotyping.

Science.gov (United States)

Vismarra, A; Barilli, E; Miceli, M; Mangia, C; Genchi, M; Brindani, F; Kramer, L; Bacci, C

2017-08-30

Toxoplasma gondii is considered one of the most important food-borne parasitic zoonoses globally and sheep are important intermediate hosts of the parasite. Meat and milk from infected sheep are considered an important source of infection for humans. Here, the authors evaluated T. gondii infection in the Italian Cornigliese sheep breed using meat juice ELISA, and in vitro assay for followed by Real Time-PCR and PCR-RFLP. Twenty-one hearts were collected at slaughter. Meat juice serology was carried out on all samples, while eleven hearts with the highest antibody titres were subjected to acid-peptic digestion and seeding onto Vero cells. DNA was extracted at three different time points following seeding. PCR-positive samples were then genotyped by PCR-RFLP. All the meat juice samples were positive for IgG antibodies against p30 protein of T. gondii. Five of the 11 samples, seeded onto Vero cells, were positive in PCR made on DNA extracted after 21days of culture and the PCR-RFLP revealed a Type-II or Type II variant profile at 9/10 loci. Two out of five samples showed an increase in terms of parasite growth by comparing the Cq values at three different time points. To the authors' knowledge, this is the first report of in vitro cultivation of T. gondii from muscle tissue of naturally-infected sheep. In vitro assays may be a promising alternative to bioassays and further studies are necessary in order to improve assay performance and to identify possible early markers of parasite proliferation. Copyright © 2017 Elsevier B.V. All rights reserved.

A qualitative assessment of Toxoplasma gondii risk in ready-to-eat smallgoods processing.

Science.gov (United States)

Mie, Tanya; Pointon, Andrew M; Hamilton, David R; Kiermeier, Andreas

2008-07-01

Toxoplasma gondii is one of the most common parasitic infections of humans and other warm-blooded animals. In most adults, it does not cause serious illness, but severe disease may result from infection in fetuses and immunocompromised people. Consumption of raw or undercooked meats has consistently been identified as an important source of exposure to T. gondii. Several studies indicate the potential failure to inactivate T. gondii in the processes of cured meat products, This article presents a qualitative risk-based assessment of the processing of ready-to-eat smallgoods, which include cooked or uncooked fermented meat, pâté, dried meat, slow cured meat, luncheon meat, and cooked muscle meat including ham and roast beef. The raw meat ingredients are rated with respect to their likelihood of containing T. gondii cysts and an adjustment is made based on whether all the meat from a particular source is frozen. Next, the effectiveness of common processing steps to inactivate T. gondii cysts is assessed, including addition of spices, nitrates, nitrites and salt, use of fermentation, smoking and heat treatment, and the time and temperature during maturation. It is concluded that processing steps that may be effective in the inactivation of T. gondii cysts include freezing, heat treatment, and cooking, and the interaction between salt concentration, maturation time, and temperature. The assessment is illustrated using a Microsoft Excel-based software tool that was developed to facilitate the easy assessment of four hypothetical smallgoods products.

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.

Toxoplasma gondii transmission by artificial insemination in sheep with experimentally contaminated frozen semen.

Science.gov (United States)

Consalter, Angélica; Silva, Andressa F; Frazão-Teixeira, Edwards; Matos, Luis F; de Oliveira, Francisco C R; Leite, Juliana S; Silva, Franciele B F; Ferreira, Ana M R

2017-03-01

Toxoplasma gondii is a parasite considered one of the major causes of reproductive problems in sheep. Furthermore, the presence of the agent in ram semen urges the possibility of sexual transmission in this species. The aim of this study was to evaluate if ram's frozen semen spiked with T. gondii tachyzoites would be able to cause infection in sheep by laparoscopic artificial insemination (AI). Nine ewes tested seronegative to anti-T. gondii antibodies by the modified agglutination test (MAT) were superovulated and inseminated to collect embryos. Animals were divided into two groups: G1 (n = 5), ewes inseminated with semen containing 4 × 10 7 tachyzoites; and G2 (n = 4), ewes inseminated with tachyzoite-free semen (control group). To confirm infection, ewe's blood samples were collected on days -14, -7, 0, 7, 14, 21, 28, 35, 49 and 57 after AI for analysis by MAT and PCR. Tissue samples of these ewes were also collected for histopathology and immunohistochemistry (IHC). Seven days after AI, all ewes of group G1 had specific antibodies to T. gondii, while those of G2 were negative. Toxoplasma gondii DNA was detected in the blood of one ewe and parasites were observed in tissues of all five animals inseminated with contaminated semen, indicating that semen freezing protocol does not affect T. gondii transmission by artificial insemination in sheep. Copyright © 2016 Elsevier Inc. All rights reserved.

The common parasite Toxoplasma gondii induces prostatic inflammation and microglandular hyperplasia in a mouse model.

Science.gov (United States)

Colinot, Darrelle L; Garbuz, Tamila; Bosland, Maarten C; Wang, Liang; Rice, Susan E; Sullivan, William J; Arrizabalaga, Gustavo; Jerde, Travis J

2017-07-01

Inflammation is the most prevalent and widespread histological finding in the human prostate, and associates with the development and progression of benign prostatic hyperplasia and prostate cancer. Several factors have been hypothesized to cause inflammation, yet the role each may play in the etiology of prostatic inflammation remains unclear. This study examined the possibility that the common protozoan parasite Toxoplasma gondii induces prostatic inflammation and reactive hyperplasia in a mouse model. Male mice were infected systemically with T. gondii parasites and prostatic inflammation was scored based on severity and focality of infiltrating leukocytes and epithelial hyperplasia. We characterized inflammatory cells with flow cytometry and the resulting epithelial proliferation with bromodeoxyuridine (BrdU) incorporation. We found that T. gondii infects the mouse prostate within the first 14 days of infection and can establish parasite cysts that persist for at least 60 days. T. gondii infection induces a substantial and chronic inflammatory reaction in the mouse prostate characterized by monocytic and lymphocytic inflammatory infiltrate. T. gondii-induced inflammation results in reactive hyperplasia, involving basal and luminal epithelial proliferation, and the exhibition of proliferative inflammatory microglandular hyperplasia in inflamed mouse prostates. This study identifies the common parasite T. gondii as a new trigger of prostatic inflammation, which we used to develop a novel mouse model of prostatic inflammation. This is the first report that T. gondii chronically encysts and induces chronic inflammation within the prostate of any species. Furthermore, T. gondii-induced prostatic inflammation persists and progresses without genetic manipulation in mice, offering a powerful new mouse model for the study of chronic prostatic inflammation and microglandular hyperplasia. © 2017 Wiley Periodicals, Inc.

Seroprevalence and Associated Risk Factors for Toxoplasma gondii Infection in Healthy Blood Donors: A Cross-Sectional Study in Sonora, Mexico.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Rascón-Careaga, Antonio; Hernández-Tinoco, Jesús; Corella-Madueño, María Alba Guadalupe; Sánchez-Anguiano, Luis Francisco; Aldana-Madrid, María Lourdes; Velasquez-Vega, Edgar; Quizán-Plata, Trinidad; Navarro-Henze, José Luis; Badell-Luzardo, Joel Alberto; Gastélum-Cano, José María; Liesenfeld, Oliver

2016-01-01

Toxoplasma gondii (T. gondii) can be transmitted by blood transfusion. We determined the prevalence of T. gondii infection in healthy blood donors in Hermosillo city, Mexico, and the association of infection with T. gondii with the sociodemographic, clinical, and behavioral characteristics of blood donors. Four hundred and eight blood donors who attended two public blood banks in Hermosillo city were examined for anti-T. gondii IgG and IgM antibodies by using enzyme-linked immunoassays. Of the 408 blood donors (mean age 31.77 ± 9.52; range 18-60 years old) studied, 55 (13.5%) were positive for anti-T. gondii IgG antibodies, and 12 (21.8%) of them were also positive for anti-T. gondii IgM antibodies. Multivariate analysis showed that seropositivity to T. gondii was associated with age (OR = 1.74; 95% CI: 1.03-2.94; P = 0.03) and tobacco use (OR = 2.09; 95% CI: 1.02-4.29; P = 0.04). Seropositivity to T. gondii was correlated with the number of pregnancies, deliveries, and cesarean sections. The seroprevalence of T. gondii infection in blood donors in Sonora is the highest reported in blood donors in northern Mexico so far. This is the first report of an association of T. gondii exposure and tobacco use. Further research to confirm this association is needed.

In silico and in vivo analysis of Toxoplasma gondii epitopes by correlating survival data with peptide-MHC-I binding affinities.

Science.gov (United States)

Huang, Si-Yang; Jensen, Maria Risager; Rosenberg, Carina Agerbo; Zhu, Xing-Quan; Petersen, Eskild; Vorup-Jensen, Thomas

2016-07-01

Protein antigens comprising peptide motifs with high binding affinity to major histocompatibility complex class I (MHC-I) molecules are expected to induce a stronger cytotoxic T-lymphocyte response and thus provide better protection against infection with microorganisms where cytotoxic T-cells are the main effector arm of the immune system. Data on cyst formation and survival were extracted from past studies on the DNA immunization of mice with plasmids coding for Toxoplasma gondii antigens. From in silico analyses of the vaccine antigens, the correlation was tested between the predicted affinity for MHC-I molecules of the vaccine peptides and the survival of immunized mice after challenge with T. gondii. ELISPOT analysis was used for the experimental testing of peptide immunogenicity. Predictions for the Db MHC-I molecule produced a strong, negative correlation between survival and the dissociation constant of vaccine-derived peptides. The in silico analyses of nine T. gondii antigens identified peptides with a predicted dissociation constant in the interval from 10nM to 40μM. ELISPOT assays with splenocytes from T. gondii-infected mice further supported the importance of the peptide affinity for MHC-I. In silico analysis clearly helped the search for protective vaccine antigens. The ELISPOT analysis confirmed that the predicted T-cell epitopes were immunogenic by their ability to release interferon gamma in spleen cells. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Kinetic mechanism of Toxoplasma gondii adenosine kinase and the highly efficient utilization of adenosine

Science.gov (United States)

Naguib, Fardos N. M.; Rais, Reem H.; Al Safarjalani, Omar N.; el Kouni, Mahmoud H.

2015-01-01

Toxoplasma gondii has an extraordinarily ability to utilize adenosine (Ado) as the primary source of all necessary purines in this parasite which lacks de novo purine biosynthesis. The activity of T. gondii adenosine kinase (TgAK, EC 2.7.1.20) is responsible for this efficient salvage of Ado in T. gondii. To fully understand this remarkable efficiency of TgAK in the utilization of Ado, complete kinetic parameters of this enzyme are necessary. Initial velocity and product inhibition studies of TgAK demonstrated that the basic mechanism of this enzyme is a hybrid random bi-uni ping-pong uni-bi. Initial velocity studies showed an intersecting pattern, consistent with substrate-enzyme-co-substrate complex formation and a binding pattern indicating that binding of the substrate interferes with the binding of the co-substrate and vice versa. Estimated kinetic parameters were KAdo = 0.002 ± 0.0002 mM, KATP = 0.05 ± 0.008 mM, and Vmax = 920 ± 35 μmol/min/mg protein. Ado exhibited substrate inhibition suggesting the presence of more than one binding site for Ado on the enzyme. ATP relieved substrate inhibition by Ado. Thus, Ado also binds to the ATP binding site. AMP was competitive with ATP, inferring that AMP binds to the same site as ATP. AMP, ADP and ATP were non-competitive with Ado, therefore, none of these nucleotides binds to the Ado binding site. Combining ATP with ADP was additive. Therefore, the binding of either ATP or ADP does not interfere with the binding of the other. It is concluded that for every ATP consumed, TgAK generates three new AMPs. These findings along with the fact that a wide range of nucleoside 5′-mono, di, and triphosphates could substitute for ATP as phosphate donors in this reaction may explain the efficient and central role played by TgAK in the utilization of Ado as the major source from which all other purines can be synthesized in T. gondii. PMID:26112826

Seroprevalence of Toxoplasma gondii and Neospora caninum infections in goats from two Argentinean provinces

Directory of Open Access Journals (Sweden)

María Laura Gos

2017-11-01

Full Text Available 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 assayed by indirect fluorescence antibody test (IFAT, cut-off 1:100 for antibodies to T. gondii and N. caninum. Seroprevalence was 40.8% (CI 39.0%-42.6% and 5.5% (CI 4.7%-6.4% for T. gondii and N. caninum, respectively. The seropositivity for both infections was higher in goats from dairy farms, resulting as follows: for T. gondii 32.7% (CI 30.8%-34.8% in extensive farms and 59.3% (CI 56.1%-62.6% in dairy farms and for N. caninum 4.1% (CI 3.2%-4.9% in extensive farms and 8.8% (CI 6.9%-10.7% in dairy farms. This is the first extensive seroepidemiology investigation for T. gondii and N. caninum in goats in Argentina.

Computational Prediction of MicroRNAs from Toxoplasma gondii Potentially Regulating the Hosts’ Gene Expression

Directory of Open Access Journals (Sweden)

Müşerref Duygu Saçar

2014-10-01

Full Text Available MicroRNAs (miRNAs were discovered two decades ago, yet there is still a great need for further studies elucidating their genesis and targeting in different phyla. Since experimental discovery and validation of miRNAs is difficult, computational predictions are indispensable and today most computational approaches employ machine learning. Toxoplasma gondii, a parasite residing within the cells of its hosts like human, uses miRNAs for its post-transcriptional gene regulation. It may also regulate its hosts’ gene expression, which has been shown in brain cancer. Since previous studies have shown that overexpressed miRNAs within the host are causal for disease onset, we hypothesized that T. gondii could export miRNAs into its host cell. We computationally predicted all hairpins from the genome of T. gondii and used mouse and human models to filter possible candidates. These were then further compared to known miRNAs in human and rodents and their expression was examined for T. gondii grown in mouse and human hosts, respectively. We found that among the millions of potential hairpins in T. gondii, only a few thousand pass filtering using a human or mouse model and that even fewer of those are expressed. Since they are expressed and differentially expressed in rodents and human, we suggest that there is a chance that T. gondii may export miRNAs into its hosts for direct regulation.

Inactivation of Toxoplasma gondii on blueberries using low dose irradiation without affecting quality

Science.gov (United States)

Toxoplasma gondii is a common protozoan parasite, whose environmentally-resistant stage, the oocyst, can contaminate irrigation water and fresh edible produce. Current washing steps in produce processing may not be effective for eliminating T. gondii from at-risk varieties of produce. The objective ...

Prevalence of Toxoplasma gondii IgG and IgM and associated risk ...

African Journals Online (AJOL)

Prevalence of Toxoplasma gondii IgG and IgM and associated risk factors among HIV-positive and HIV-negative patients in Vhembe district of South Africa. ... shown a high prevalence of T. gondii (IgG) among patients attending different HIV clinics in the Vhembe district with no current infections among pregnant women.

Atypical Toxoplasma gondii genotype in feral cats from the Fernando de Noronha Island, northeastern Brazil.

Science.gov (United States)

Melo, R P B; Almeida, J C; Lima, D C V; Pedrosa, C M; Magalhães, F J R; Alcântara, A M; Barros, L D; Vieira, R F C; Garcia, J L; Mota, R A

2016-07-15

Toxoplasma gondii isolates from Brazil have a different phenotypic and genotypic pattern, with predominance of virulent isolates and recombinant genotypes, compared to the North Hemisphere. Considering that a new T. gondii genotype, non-pathogenic to mice, was previously identified from free-range chickens from the Fernando de Noronha Island, Brazil, this study aimed to identify genotypes of this parasite in tissue samples of feral cats (Felis catus) from this Brazilian Island. Anti-T. gondii IgG antibodies were detected in 18/31 (58%) feral cats. Two non-virulent T. gondii isolates were obtained by mouse bioassay. Genotyping was performed by PCR-RFLP using 10 genetic markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, PK1, L358 and Apico) and an atypical strain of T. gondii (ToxoDB #146) was identified. This is the first report of this genotype in feral cats. Copyright © 2016 Elsevier B.V. All rights reserved.

Infection rate of toxoplasma gondii and age distribution in female patients with sterility

International Nuclear Information System (INIS)

Li Shuhong; Dai Pei; Cui Liming; Zong Shan; Zuo Wenjing

2006-01-01

Objective: To discuss the relationship between the infection of Toxoplasma gondii and female sterility. Methods: Toxoplasma gondii serum antibody were determined in 882 women with sterility (experimental group) and 107 normal bearing women (control group) by using ELISA. At the same time the differences of the infection with Toxoplasma gondii between the ages of the sterility women were analyzed. Results: The positive rate in experimental group was 15.87% (140/882), the positive rate in control group was 5.61% (6/107), remarkable difference was found between two groups (P<0.01). The infection rate in the different age groups (20-24, 25-29, 30-34, 35-39 and ≥40) is 5.63%, 15.24%, 17.91%, 19.44% and 15.38%. Conclusion: Toxoplasma gondii infection may be one of the factors which can cause sterility, and the infection rates at different ages have no instinct differences. (authors)

Recombinant canine adenovirus type-2 expressing TgROP16 provides partial protection against acute Toxoplasma gondii infection in mice.

Science.gov (United States)

Li, Xiu-Zhen; Lv, Lin; Zhang, Xu; Anchang, Kenneth Yongabi; Abdullahi, Auwalu Yusuf; Tu, Liqing; Wang, Xiaohu; Xia, Lijun; Zhang, Xiu-Xiang; Feng, Weili; Lu, Chunxia; Li, Shoujun; Yuan, Zi-Guo

2016-11-01

We previously demonstrated that the survival time of BALB/c mice challenged with Toxoplasma gondii RH strain was prolonged by immunising the mice with a eukaryotic vector expressing the protein ROP16 of T. gondii. Building upon previous findings, we are exploring improved vaccination strategies to enhance protection. In this work, a novel recombinant canine adenovirus type 2 expressing ROP16 (CAV-2-ROP16) of T. gondii was constructed and identified to express ROP16 in Madin-Darby canine kidney cells (MDCK) cells by western blot (WB) and indirect immunofluorescence (IFA) assays. Intramuscular immunisation of BALB/c mice with CAV-2-ROP16 was performed to evaluate the humoral and cellular immune responses. This vaccination triggered significant humoral and cellular responses, including ROP16-stimulated lymphoproliferation (P0.05), revealing that a predominant Th1-type response had developed. The cell-mediated cytotoxic activity with high levels of IFN-γ and TNF-α was significantly increased in both CD4 + and CD8 + T-cell compartments in the mice immunised with CAV-2-ROP16 (Pdays post infection compared with control mice that all died within seven days (Pvaccination until now. Our work presents the successful use of recombinant virus CAV-2-ROP16 in vaccination protocols to protect against intraperitoneal challenge with the virulent RH strain of T. gondii. This system was shown to be extremely efficient in eliciting humoral and cellular immune responses that led to a significant improvement in survival time in mice. Copyright © 2016 Elsevier B.V. All rights reserved.

Seropositivity and risk factors associated with Toxoplasma gondii infection in wild birds from Spain.

Directory of Open Access Journals (Sweden)

Oscar Cabezón

Full Text Available Toxoplasma gondii is a zoonotic intracellular protozoan parasite of worldwide distribution that infects many species of warm-blooded animals, including birds. To date, there is scant information about the seropositivity of T. gondii and the risk factors associated with T. gondii infection in wild bird populations. In the present study, T. gondii infection was evaluated on sera obtained from 1079 wild birds belonging to 56 species (including Falconiformes (n=610, Strigiformes (n=260, Ciconiiformes (n=156, Gruiformes (n=21, and other orders (n=32, from different areas of Spain. Antibodies to T. gondii (modified agglutination test, MAT titer ≥1:25 were found in 282 (26.1%, IC(95%:23.5-28.7 of the 1079 birds. This study constitute the first extensive survey in wild birds species in Spain and reports for the first time T. gondii antibodies in the griffon vulture (Gyps fulvus, short-toed snake-eagle (Circaetus gallicus, Bonelli's eagle (Aquila fasciata, golden eagle (Aquila chrysaetos, bearded vulture (Gypaetus barbatus, osprey (Pandion haliaetus, Montagu's harrier (Circus pygargus, Western marsh-harrier (Circus aeruginosus, peregrine falcon (Falco peregrinus, long-eared owl (Asio otus, common scops owl (Otus scops, Eurasian spoonbill (Platalea leucorodia, white stork (Ciconia ciconia, grey heron (Ardea cinerea, common moorhen (Gallinula chloropus; in the International Union for Conservation of Nature (IUCN "vulnerable" Spanish imperial eagle (Aquila adalberti, lesser kestrel (Falco naumanni and great bustard (Otis tarda; and in the IUCN "near threatened" red kite (Milvus milvus. The highest seropositivity by species was observed in the Eurasian eagle owl (Bubo bubo (68.1%, 98 of 144. The main risk factors associated with T. gondii seropositivity in wild birds were age and diet, with the highest exposure in older animals and in carnivorous wild birds. The results showed that T. gondii infection is widespread and can be at a high level in many wild

Anti-Toxoplasma gondii secretory IgA in tears of patients with ocular toxoplasmosis: immunodiagnostic validation by ELISA

OpenAIRE

Lynch,Maria Isabel; Malagueño,Elizabeth; Lynch,Luiz Felipe; Ferreira,Silvana; Stheling,Raphael; Oréfice,Fernando

2009-01-01

Toxoplasma gondii causes posterior uveitis and the specific diagnosis is based on clinical criteria. The presence of anti-T. gondii secretory IgA (sIgA) antibodies in patients' tears has been reported and an association was found between ocular toxoplasmosis and the anti-T. gondii sIgA isotype in Brazilian patients. The purpose of this study was to provide an objective validation of the published ELISA test for determining the presence of anti-T. gondii sIgA in the tears of individuals with o...

First report of Toxoplasma gondii infection in market-sold adult chickens, ducks and pigeons in northwest China

Directory of Open Access Journals (Sweden)

Cong Wei

2012-06-01

Full Text Available Abstract Background Toxoplasma gondii infection is a global concern, affecting a wide range of warm-blooded animals and humans worldwide, including poultry. Domestic and companion birds are considered to play an important role in the transmission of T. gondii to humans and other animals. However, little information on T. gondii infection in domestic birds in Lanzhou, northwest China was available. Therefore, this study was performed to determine the seroprevalence of T. gondii infection in domestic birds in Lanzhou, northwest China. Methods In the present study, the seroprevalence of T. gondii antibodies in 413 (305 caged and 108 free-range adult chickens, 334 (111 caged and 223 free-range adult ducks and 312 adult pigeons in Lanzhou, northwest China, were examined using the modified agglutination test (MAT. Results 30 (7.26% chickens, 38 (11.38% ducks and 37 (11.86% pigeons were found to be positive for T. gondii antibodies at the cut-off of 1:5. The prevalences in caged and free-range chickens were 6.23% and 10.19% respectively, however, statistical analysis showed that the difference was not significant (P > 0.05. The seroprevalences in caged and free-range ducks were 6.31% and 13.90% respectively, but the difference was not statistically significant (P > 0.05. Conclusions The results of the present survey indicated the presence of T. gondii infection in adult chickens, ducks and pigeons sold for meat in poultry markets in Lanzhou, northwest China, which poses a potential risk for T. gondii infection in humans and other animals in this region. This is the first seroprevalence study of T. gondii infection in domestic birds in this region.

A quantitative microbial risk assessment for meatborne Toxoplasma gondii infection in The Netherlands

NARCIS (Netherlands)

Opsteegh, M.; Prickaerts, S.; Frankena, K.; Evers, E.G.

2011-01-01

Toxoplasma gondii is an important foodborne pathogen, and the cause of a high disease burden due to congenital toxoplasmosis in The Netherlands. The aim of this study was to quantify the relative contribution of sheep, beef and pork products to human T. gondii infections by Quantitative Microbial

The first isolation and molecular characterization of Toxoplasma gondii from horses in Serbia.

NARCIS (Netherlands)

Klun, Ivana; Uzelac, Aleksandra; Villena, Isabelle; Mercier, Aurélien; Bobić, Branko; Nikolić, Aleksandra; Rajnpreht, Irena; Opsteegh, Marieke; Aubert, Dominique; Blaga, Radu; van der Giessen, Joke; Djurković-Djaković, Olgica

2017-01-01

Consumption of undercooked or insufficiently cured meat is a major risk factor for human infection with Toxoplasma gondii. Although horsemeat is typically consumed rare or undercooked, information on the risk of T. gondii from infected horse meat to humans is scarce. Here, we present the results of

Seroprevalence and isolation of viable Toxoplasma gondii from raptors in the southeastern USA

Science.gov (United States)

Raptors are good indicators of the prevalence of Toxoplasma gondii in the environment because they prey on small mammals and birds. These prey species are a major source of infection in felids, which shed the environmentally resistant oocysts. We assessed T. gondii infection in 281 opportunistically...

A meta-analysis of the prevalence of toxoplasma gondii igg antibodies in patients with mental disorders

Directory of Open Access Journals (Sweden)

Angela Dragomir1,

2016-12-01

Full Text Available OBJECTIVES AND BACKGROUND Toxoplasma gondii infection has been recently associated with schizophrenia and other psychiatric disorders. The aim of the present study was to evaluate the prevalence of T. gondii infection in psychiatric patients by using meta-analytical methods. MATERIALS AND METHODS By systematic research of PUBMED Database, we identified several articles on this issue. We included casecontrol studies focused on the seroprevalence of T. gondii (IgG antibodies in patients with psychiatric disorders and healthy controls, published over the past 10 years R3.2.2. free software for statistical computing and graphics was used to perform the meta-analysis. Data were pooled using a random effects model and Mantel-Haenszel method. RESULTS The PUBMED Database showed references to only seven scientific papers that investigated the prevalence of T. gondii IgG antibodies in psychiatric patients. Six hundred seventy three patients and seven hundred seventy four controls coped with the inclusion criteria and were used in our analysis. We found a significant increase of T. gondii IgG antibodies in patients with schizophrenia and other psychiatric disorders compared with controls (41.6% vs 24.54%, OR = 2.16, 95% CI = [1.45-3.21], P = .001. CONCLUSIONS An increased seroprevalence of T. gondii IgG antibodies has been reported in psychiatric patients. Our study suggests that T. gondii infection may be relevant in order to determine and understand the complex etiology of schizophrenia and other psychiatric disorders. Graphical abstract: Meta-analysis of the prevalence of T. gondii IgG antibodies in patients with mental disorders REFERENCES 1. Hamidinejat H, Ghorbanpoor M, Hosseini H, Alavi SM, Nabavi L, Jalali MH, Borojeni MP, Jafari H, Mohammadaligol S. Toxoplasma gondii infection in first-episode and inpatient individuals with schizophrenia. Int J Infect Dis. 2010;14:e978-81. doi: 10.1016/j.ijid.2010.05.018. 2. Alvarado-Esquivel C, Carrillo-Oropeza D

Canine distemper virus and Toxoplasma gondii co-infection in dogs with neurological signs

Directory of Open Access Journals (Sweden)

D.M. Aguiar

2012-02-01

Full Text Available O presente estudo relata a ocorrência de co-infecção entre o vírus da cinomose canina (CDV e Toxoplama gondii em cães com sinais neurológicos. Amostras de soro e tecido nervoso (pos-mortem de 21 cães, suspeitos de cinomose canina foram analisadas pela Reação de Imunofluorecência indireta (RIFI para pesquisa de anticorpos contra T. gondii e N. caninum e por RT-PCR para CDV. Dezessete (80,9% cães foram positivos para o CDV pela RT-PCR e 8 (38,1% foram positivos para anticorpos contra T. gondii. Sete cães (41,1% apresentaram-se positivos para ambos agentes, caracterizando processo de co-infecção. Somente 1 (4,7% cão foi soropositivo para N. caninum (RIFI=100, entretanto este mesmo animal foi positivo para T. gondii (RIFI=4096 e para CDV (RT-PCR.

Seroepidemiology of Toxoplasma gondii Infection in Women of Reproductive Age: A Cross-Sectional Study in a Northwestern Mexican City

Science.gov (United States)

Alvarado-Esquivel, Cosme; Corella-Madueno, Maria Alba Guadalupe; Hernandez-Tinoco, Jesus; Rascon-Careaga, Antonio; Sanchez-Anguiano, Luis Francisco; Martinez-Robinson, Karla Guadalupe; Aldana-Madrid, Maria Lourdes; Quizan-Plata, Trinidad; Canez-Carrasco, Maria Guadalupe; Perez-Martinez, Cinthia Jhovanna

2018-01-01

Background Through a cross-sectional survey, we determined the seroprevalence and correlates of Toxoplasma gondii (T. gondii) infection in women of reproductive age in Hermosillo City, Mexico. Methods We studied 445 women of reproductive age in Hermosillo City in the northwestern Mexican state of Sonora. Women were enrolled in the University of Sonora. Sera of women were examined for IgG and IgM antibodies to T. gondii by commercially available enzyme immunoassays. The association of T. gondii seropositivity with the characteristics of the pregnant women was determined by bivariate and multivariate analyses. Results Of the 445 women (mean age: 22.18 ± 5.6 years) studied, 16 (3.6%) had IgG antibodies to T. gondii, and two (12.5%) were also positive for IgM antibodies to T. gondii. Of the 16 anti-T. gondii IgG-positive women, six (37.5%) had IgG levels higher than 150 IU/mL, four (25.0%) between 100 and 150 IU/mL, and six (37.5%) between 9 and 99 IU/mL. Multivariate analysis of socio-demographic and behavioral variables showed that T. gondii seropositivity was associated with older age (odds ratio (OR): 5.30; 95% confidence interval (CI): 1.37 - 20.50; P = 0.01) and boar meat consumption (OR: 6.86; 95% CI: 1.27 - 37.07; P = 0.02). Conclusions Women of reproductive age in Hermosillo City had a low seroprevalence of T. gondii infection. However, this finding indicates that most of these women were susceptible to a primary infection. Factors associated with T. gondii infection found in this study may be useful for the optimal planning of preventive measures against T. gondii infection and its sequelae. PMID:29416579

Seroprevalence of Toxoplasma gondii Infection in Patients of Intensive Care Unit in China: A Hospital Based Study

Directory of Open Access Journals (Sweden)

Yong-Biao Zhang

2015-01-01

Full Text Available The objective of this study was to estimate the seroprevalence of Toxoplasma gondii infection in 394 patients of intensive care unit (ICU in a hospital between April 2010 and March 2012 and analyze the association between T. gondii infection and ICU patients according to the species of disease. Toxoplasma serology was evaluated by ELISA method using a commercially available kit. Data of patients were obtained from the patients, informants, and medical examination records. Seventy-four (18.78% of 394 patients were positive for anti-T. gondii IgG antibodies demonstrating latent infection. Of these, the highest T. gondii seroprevalence was found in the age group of 31–45 years (27.45%, and the lowest was found in the age group of <30 years (12.5%. In addition, females (21.6% had a higher seroprevalence than males (18.36%. With respect to the species of disease, the patients with kidney diseases (57.14%, lung diseases (27.84%, and brain diseases (24% had high T. gondii seroprevalence. The present study represents the first survey of T. gondii seroprevalence in ICU patients in China, revealing an 18.78% seropositivity. Considering the particularities of ICU patients, molecular identification, genetic characterization, and diagnosis of T. gondii should be considered in future study.

Prevalence of Toxoplasma gondii in Chicken samples from delta of Egypt using ELISA, histopathology and immunohistochemistry.

Science.gov (United States)

Ibrahim, Hany M; Abdel-Ghaffar, Fathy; Osman, Gamalat Y; El-Shourbagy, Safinaz H; Nishikawa, Yoshifumi; Khattab, Reham A

2016-06-01

Estimates of the zoonotic diseases are helpful for monitoring and improving public health. Laboratory-based surveillance provides crucial information for assessing zoonotic disease trends and developments. Toxoplasmosis is considered as a zoonotic disease and has both medical and veterinary importance since it leads to abortion in humans and several animal species. In view of the worldwide importance of T. gondii, this study aimed to estimate the prevalence of T. gondii in chickens from the Delta of Egypt. A total of 304 blood and brain samples were collected from Egyptian chickens from Gharbiya, Qalyoubiya, Minufiya, Beheira, Kafr EL-Shaykh and Dakahlia Provinces. In order to determine the serological and histopathological prevalence of T. gondii, the samples were examined by ELISA, histopathology and immunohistochemistry (IHC). The prevalence of T. gondii was 11.18, 6.91, 6.91 % by ELISA, histopathology and IHC, respectively. Statistically significant differences in the prevalence of T. gondii were observed on the basis of season, sex and habitat. These data provide valuable information regarding the epidemiology of T. gondii infections in Egyptian chickens, which can be employed in developing efficient strategies for disease management and control.

Toxoplasma gondii and Epilepsy.

Science.gov (United States)

Ayaz, Erol; Türkoğlu, Şule Aydın; Orallar, Hayriye

2016-06-01

Toxoplasma gondii is a zoonotic parasite can be seen in all the vital organ; in the acute phase, it can be found in the blood, cerebrospinal fluid, semen, tears, saliva, urine, and in almost all body fluids. Transplasental infection can lead to fetal damage and miscarriage. Its last hosts are felines and intermediate hosts are all mammals, including humans. People infected by the ingestion of meat containing cysts in undercooked or raw, are thrown oocysts with cat felines By taking in water and food, from mother to fetus transplacental way, the infected organ transplantation, blood transfusion, laboratory accidents and kaprofaj transmitted by mechanical vectors of the invertebrates. Suppression of the immune system is being transformed to the shape and texture of the cysts with bradyzoite. The parasite settles in the cells of the tissue cysts and causes change in the cellular mechanisms, such as cytokinin task. Depending on changes and type of neurotransmitter (GABA, glutamate, serotonin, dopamine) levels in CSF in ions (Ca, K, Cl, Mg), it is believed that there is a change in their concentration. In this review, literature about the relationship between T. gondii and epilepsy and epileptiform activity the importance of parasites, which settle in the brain, will be highlighted.

New, previously unreported correlations between latent Toxoplasma gondii infection and excessive ethanol consumption.

Science.gov (United States)

Samojłowicz, Dorota; Borowska-Solonynko, Aleksandra; Kruczyk, Marcin

2017-11-01

A number of world literature reports indicate that a latent Toxoplasma gondii infection leads to development of central nervous system disorders, which in turn may lead to altered behavior in the affected individuals. T. gondii infection has been observed to play the greatest role in drivers, suicides, and psychiatric patients. Studies conducted for this manuscript involve a different, never before really reported correlation between latent T. gondii infection and ethanol abuse. A total of 538 decedents with a known cause of death were included in the study. These individuals were divided into three groups: the risky behavior group, inconclusively risky behavior group, and control group. The criterion for this division was the likely effect of the individual's behavior on the mechanism and cause of his/her death. The material used for analyses were blood samples collected during routine medico-legal examinations in these cases. The blood samples were used to measure anti-T. gondii IgG antibodies with an enzyme-linked immunosorbent assay (ELISA). Moreover, the following data were recorded for each decedent: sex, age, circumstances of death, cause of death, time from death to autopsy, and (if provided) substance abuse status (alcohol, illicit drugs). In those cases where blood alcohol level or toxicology tests were requested by the Prosecutor's Office, their results were also included in our analysis. Test results demonstrated a strong correlation between latent T. gondii infection and engaging in risky behaviors leading to death. Moreover, analyses demonstrated a positive correlation between the presence of anti-T. gondii IgG antibodies and psychoactive substance (especially ethanol) abuse, however, the causal relationship remains unclear. Due to the fact that alcohol abuse constitutes a significant social problem, searching for eliminable risk factors for addiction is extremely important. Our analyses provided new important information on the possible effects of

Low Seroprevalence of Leishmania infantum and Toxoplasma gondii in the Horse Population in Israel.

Science.gov (United States)

Aharonson-Raz, Karin; Baneth, Gad; Lopes, Ana Patrícia; Brancal, Hugo; Schallig, Henk; Cardoso, Luís; Steinman, Amir

2015-12-01

A cross-sectional investigation was done on the seroprevalence of Leishmania infantum and Toxoplasma gondii infection among apparently healthy horses in Israel. This survey included 383 horses distributed in 22 farms throughout Israel during the years 2011-2013. Serum samples were tested for the presence of immunoglobulin G (IgG) antibodies using the direct agglutination test (DAT) specific to Leishmania and by the modified agglutination test (MAT) for the presence of IgG antibodies to T. gondii. Low seroprevalences were detected for both L. infantum and T. gondii in the horse population in Israel; of the 338 horses tested, 6 (1.4%) were found to be seropositive for L. infantum and 11 (2.5%) for T. gondii, with no significant association between seroprevalence and demographic/environmental factors. An ongoing geographical expansion of L. infantum, previously reported in humans and dogs in Israel, was also supported by our results in horses. Here we present evidence of exposure of horses to L. infantum and T. gondii in Israel. Continuous seroprevalence surveillance in horses, such as the one performed in this study, might further elucidate the eco-epidemiology of these two important zoonotic parasites in this country.

Eimeria maxima microneme protein 2 delivered as DNA vaccine and recombinant protein induces immunity against experimental homogenous challenge.

Science.gov (United States)

Huang, Jingwei; Zhang, Zhenchao; Li, Menghui; Song, Xiaokai; Yan, Ruofeng; Xu, Lixin; Li, Xiangrui

2015-10-01

E. maxima is one of the seven species of Eimeria that infects chicken. Until now, only a few antigenic genes of E. maxima have been reported. In the present study, the immune protective effects against E. maxima challenge of recombinant protein and DNA vaccine encoding EmMIC2 were evaluated. Two-week-old chickens were randomly divided into five groups. The experimental group of chickens was immunized with 100 μg DNA vaccine pVAX1-MIC2 or 200 μg rEmMIC2 protein while the control group of chickens was injected with pVAX1 plasmid or sterile PBS. The results showed that the anti-EmMIC2 antibody titers of both rEmMIC2 protein and pVAX1-MIC2 groups were significantly higher as compared to PBS and pVAX1 control (Pmaxima challenge and it could be an effective antigen candidate for the development of new vaccines against E. maxima. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Prevalence of Toxoplasma gondii antibodies and intestinal parasites in stray cats from Nigde, Turkey

Directory of Open Access Journals (Sweden)

Bengi Dündar

2010-01-01

Full Text Available The prevalence of antibodies to Toxoplasma gondii was investigated by the Sabin-Feldman Dye test (SFDT in 72 stray cats from Nigde, Turkey. A total of 55 (76.4% of the analysed sera had antibodies to T. gondii. The seropositivity of T. gondii was 77.1% in male and 75.7% in female cats (P>0.05. Faeces of these cats were also examined by zinc sulphate flotation method for the presence of parasite oocysts and eggs of other parasites. Two protozoan parasites were identified as Isospora spp. (12.5% and Eimeria spp. (4.1% in cats. Toxoplasma gondii oocysts were not found in any faecal samples analysed. Two parasitic helminth species were observed: Toxocara cati (15.2% and Toxascaris leonina (20.8%. These common ascarids were recorded for the first time in cats from Nigde.

Highly diverged novel subunit composition of apicomplexan F-type ATP synthase identified from Toxoplasma gondii

KAUST Repository

Salunke, Rahul

2018-05-14

The mitochondrial F-type ATP synthase, a multi-subunit nanomotor, is critical for maintaining cellular ATP levels. In Toxoplasma gondii and other apicomplexan parasites, many subunit components, necessary for proper assembly and functioning of this enzyme, appear to be missing. Here, we report the identification of 20 novel subunits of T. gondii F-type ATP synthase from mass spectrometry analysis of partially purified monomer (~600 kDa) and dimer (>1 MDa) forms of the enzyme. Despite extreme sequence diversification, key FO subunits, a, b and d, can be identified from conserved structural features. Orthologs for these proteins are restricted to apicomplexan, chromerid and dinoflagellate species. Interestingly, their absence in ciliates indicates a major diversion, with respect to subunit composition of this enzyme, within the alveolate clade. Discovery of these highly diversified novel components of the apicomplexan F-type ATP synthase complex will facilitate the development of novel anti-parasitic agents. Structural and functional characterization of this unusual enzyme complex will advance our fundamental understanding of energy metabolism in apicomplexan species.

Highly diverged novel subunit composition of apicomplexan F-type ATP synthase identified from Toxoplasma gondii

KAUST Repository

Salunke, Rahul; Mourier, Tobias; Banerjee, Manidipa; Pain, Arnab; Shanmugam, Dhanasekaran

2018-01-01

The mitochondrial F-type ATP synthase, a multi-subunit nanomotor, is critical for maintaining cellular ATP levels. In Toxoplasma gondii and other apicomplexan parasites, many subunit components, necessary for proper assembly and functioning of this enzyme, appear to be missing. Here, we report the identification of 20 novel subunits of T. gondii F-type ATP synthase from mass spectrometry analysis of partially purified monomer (~600 kDa) and dimer (>1 MDa) forms of the enzyme. Despite extreme sequence diversification, key FO subunits, a, b and d, can be identified from conserved structural features. Orthologs for these proteins are restricted to apicomplexan, chromerid and dinoflagellate species. Interestingly, their absence in ciliates indicates a major diversion, with respect to subunit composition of this enzyme, within the alveolate clade. Discovery of these highly diversified novel components of the apicomplexan F-type ATP synthase complex will facilitate the development of novel anti-parasitic agents. Structural and functional characterization of this unusual enzyme complex will advance our fundamental understanding of energy metabolism in apicomplexan species.

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.

Toxoplasma gondii infections in sheep in Sicily, southern Italy

DEFF Research Database (Denmark)

Vesco, G; Buffolano, W; La Chiusa, S

2007-01-01

is very prevalent, and eating unprocessed sheep and lamb meat has a high risk of transmitting infections to humans. The presence of cats on the farm, farm size and using surface water as drinking water for the animals were risk factors for infection in sheep, with age as a significant confounder...... outdoor on pasture and only one was claiming organic farming. Having cats on the farm, age of the animals, farm size and the use of surface water sources for drinking were all significantly associated with T. gondii-infected animals on the farm. T. gondii infection in mutton used for human consumption...

Seroprevalence of Toxoplasma gondii in free-ranging and feral cats on Amami Oshima Island, Japan

OpenAIRE

MATSUU, Aya; YOKOTA, Shin-ichi; ITO, Keiko; MASATANI, Tatsunori

2017-01-01

On Amami Oshima Island, free-ranging and feral cats are harmful to wildlife populations. In this study, the seroprevalence of Toxoplasma gondii in these cats was examined using a newly developed Gaussia luciferase immunoprecipitation system assay. Of 1,363 cats, 123 cats (9.0%) was positive for T. gondii. The prevalence was significantly different in different areas; among cats in the rural area, where many wild animals live, including endangered species, T. gondii infection was more prevalen...

Investigating seagrass in Toxoplasma gondii transmission in Florida (Trichechus manatus latirostris) and Antillean (T. m. manatus) manatees

Science.gov (United States)

Wyrosdick, Heidi M; Gerhold, Richard; Su, Chunlei; Mignucci-Giannoni, Antonio A.; Bonde, Robert K.; Chapman, Alycia; Riviera-Perez, Carla; Martinez, Jessica; Miller, Debra L.

2017-01-01

Toxoplasma gondii is a feline protozoan reported to cause morbidity and mortality in manatees and other marine mammals. Given the herbivorous nature of manatees, ingestion of oocysts from contaminated water or seagrass is presumed to be their primary mode of infection. The objectives of this study were to investigate oocyst contamination of seagrass beds in Puerto Rico and determine the seroprevalence of T. gondii in Antillean (Trichechus manatus manatus) and Florida (T. m. latirostris) manatees. Sera or plasma from Antillean (n = 5) and Florida (n = 351) manatees were tested for T. gondii antibodies using the modified agglutination test. No T. gondii DNA was detected via PCR in seagrass samples (n = 33) collected from Puerto Rico. Seroprevalence was 0%, suggesting a lower prevalence of T. gondii in these manatee populations than previously reported. This was the first study to investigate the potential oocyst contamination of the manatee diet, and similar studies are important for understanding the epidemiology of T. gondii in herbivorous marine mammals.

Use of filter papers to determine seroprevalence of Toxoplasma gondii among hunted ungulates in remote Peruvian Amazon.

Science.gov (United States)

Aston, Emily J; Mayor, Pedro; Bowman, Dwight D; Mohammed, Hussni O; Liotta, Janice L; Kwok, Oliver; Dubey, J P

2014-04-01

Toxoplasmosis is a zoonosis caused by the protozoan Toxoplasma gondii, and it is found worldwide. To determine whether ungulates are reservoirs of T. gondii in an isolated and remote region of the northeastern Peruvian Amazon, antibodies to T. gondii were determined in 5 species of ungulates by the modified agglutination test (MAT). These animals were hunted by subsistence hunters along the Yavarí-Mirín River, in the northeastern Peruvian Amazon. Blood samples were collected by hunters on filter papers. For determination of T. gondii antibodies, blood was eluted from filter papers, and a titer of 1:25 was considered indicative of exposure to T. gondii. Antibodies to T. gondii were found in 26 (31.0%) peccaries (Pecari tajacu, Tayassu pecari), six (17.1%) brocket deer (Mazama americana, Mazama gouazoubira), and four (40.0%) lowland tapir (Tapirus terrestris). We also introduced a modification to the MAT protocol that allows the extraction of fluid samples from several types of laboratory-grade filter paper, thus enabling researchers to easily adapt their approaches to the materials presented to them.

Use of filter papers to determine seroprevalence of Toxoplasma gondii among hunted ungulates in remote Peruvian Amazon☆

Science.gov (United States)

Aston, Emily J.; Mayor, Pedro; Bowman, Dwight D.; Mohammed, Hussni O.; Liotta, Janice L.; Kwok, Oliver; Dubey, J.P.

2013-01-01

Toxoplasmosis is a zoonosis caused by the protozoan Toxoplasma gondii, and it is found worldwide. To determine whether ungulates are reservoirs of T. gondii in an isolated and remote region of the northeastern Peruvian Amazon, antibodies to T. gondii were determined in 5 species of ungulates by the modified agglutination test (MAT). These animals were hunted by subsistence hunters along the Yavarí-Mirín River, in the northeastern Peruvian Amazon. Blood samples were collected by hunters on filter papers. For determination of T. gondii antibodies, blood was eluted from filter papers, and a titer of 1:25 was considered indicative of exposure to T. gondii. Antibodies to T. gondii were found in 26 (31.0%) peccaries (Pecari tajacu, Tayassu pecari), six (17.1%) brocket deer (Mazama americana, Mazama gouazoubira), and four (40.0%) lowland tapir (Tapirus terrestris). We also introduced a modification to the MAT protocol that allows the extraction of fluid samples from several types of laboratory-grade filter paper, thus enabling researchers to easily adapt their approaches to the materials presented to them. PMID:24918073

21 CFR 866.3780 - Toxoplasma gondii serological reagents.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3780 Toxoplasma... (immunofluorescent reagents) used to identify Toxoplasma gondii from clinical specimens. The identification aids in...

Usefulness of the detection of Toxoplasma gondii antigens in AIDS patients Utilidad de la detección de antígenos de Toxoplasma gondii en pacientes con SIDA

Directory of Open Access Journals (Sweden)

Alberto Fachado

1994-12-01

Full Text Available Toxoplasmic encephalitis (TE is a mayor cause of central nervous system infection in patients with acquired immunodeficiency syndrome (AIDS. Toxoplasma antibodies were detected in 56 of 79 patients with AIDS (71%, in the present study. Fourteen out of 57 seropositive patients developed TF (25% and had Toxoplasma gondii antigen detected in their urine. For this, most of them received an effective therapy, with the subsequent disappearance of the symptoms and discontinuity of excretion of the T. gondii antigens. Our results suggest that the monitoring of T. gondii antigen in the urine of AIDS patients may be useful to decide on the proper time for therapy, as well as to avoid the beginning of neurologic signs in these patients.La Encefalitis Toxoplásmica (ET es la más importante complicación infecciosa del Sistema Nervioso Central en pacientes de SIDA. Anticuerpos anti-Toxoplasma gondii fueron detectados en 57 de 79 pacientes de SIDA (71%. De estos seropositivos, desarrollaron la enfermedad (ET 14 (25%, en los que coincidentemente se detectó la presencia de antígeno del parásito en orina y por tanto fueron objeto de una terapia efectiva, con la subsecuente desaparición de los sintomas y de los antígenos excretados. Por los resultados del presente trabajo, consideramos lo útil de monitorear en estos pacientes la presencia de antígenos de T. gondii con el objetivo de aplicar oportunamente métodos quimoprofilácticos que eviten el surgimiento de manifestaciones neurológicas en estos pacientes.

Production, characterization and applications for Toxoplasma gondii-specific polyclonal chicken egg yolk immunoglobulins.

Directory of Open Access Journals (Sweden)

Álvaro Ferreira Júnior

Full Text Available Toxoplasma gondii may cause abortions, ocular and neurological disorders in warm-blood hosts. Immunized mammals are a wide source of hyperimmune sera used in different approaches, including diagnosis and the study of host-parasite interactions. Unfortunately, mammalian antibodies present limitations for its production, such as the necessity for animal bleeding, low yield, interference with rheumatoid factor, complement activation and affinity to Fc mammalian receptors. IgY antibodies avoid those limitations; therefore they could be an alternative to be applied in T. gondii model.In this study we immunized hens with soluble tachyzoite antigens of T. gondii (STAg and purified egg yolk antibodies (IgY by an inexpensive and simple method, with high yield and purity degree. IgY anti-STAg antibodies presented high avidity and were able to recognize a broad range of parasite antigens, although some marked differences were observed in reactivity profile between antibodies produced in immunized hens and mice. Interestingly, IgY antibodies against Neospora caninum and Eimeria spp. did not react to STAg. We also show that IgY antibodies were suitable to detect T. gondii forms in paraffin-embedded sections and culture cell monolayers.Due to its cost-effectiveness, high production yield and varied range of possible applications, polyclonal IgY antibodies are useful tools for studies involving T. gondii.

Molecular Cloning, Expression and Characterization of Plasmid Encoding Rhomboid 4 (ROM4 of Tachyzoite of Toxoplasma gondii RH Strain

Directory of Open Access Journals (Sweden)

Mohammad Taghi RAHIMI

2017-12-01

Full Text Available AbstractBackground: The objective of this study was to clone, express and characterize the gene encoding rhomboid 4 (ROM4 proteins, a vital gene in surface adhesion and host cell invasion process of tachyzoite of T. gondii in an appropriate expression vector and eukaryotic cell for production of recombinant protein.Methods: Toxoplasma RNA was isolated from tachyzoites (RH strain and complementary DNA was synthesized. Oligonucleotide primer pair was designed based on Toxoplasma ROM4 gene sequence with XhoI and EcoRI restriction sites at 5´ end of forward and reverse primers, respectively. ROM4 gene was amplified by PCR, cloned into pTG19-T vector and the recombinant plasmid was sequenced. The gene was subcloned into pcDNA3 plasmid and expressed in CHO cells as eukaryotic cell. SDS-PAGE and western blotting were performed for protein determination and verification.Results: Cloning of ROM4 gene in pTG19-T vector was confirmed by colony-PCR and enzymatic digestion. The results of enzymatic digestion and gene sequencing confirmed successful cloning and subcloning procedures. The nucleotide sequence of the cloned ROM4 gene showed 99% homology compared to the corresponding sequences of original gene. SDS-PAGE and western blotting analyses of the purified protein revealed a single band having expected size of 65 kDa.Conclusion: This eukaryotic expression system is an appropriate system for high-level recombinant protein production of ROM4 gene from T. gondii tachyzoites used as antigenic component for serological assay and vaccine development.

High prevalence of toxoplasmosis in cats from Egypt: isolation of viable Toxoplasma Gondii, tissue distribution, and isolate designation

Science.gov (United States)

Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that excrete environmentally resistant oocysts in feces. In the present study, 158 feral cats from Giza, Egypt were examined for T. gondii infection. Antibodies to T. gondii were found in 97.4% with modified ...

Pathology, clinical signs, and tissue distribution of Toxoplasma gondii in experimentally infected reindeer (Rangifer tarandus

Directory of Open Access Journals (Sweden)

Émilie Bouchard

2017-12-01

Full Text Available Toxoplasma gondii is a zoonotic parasite found in vertebrates worldwide for which felids serve as definitive hosts. Despite low densities of felids in northern Canada, Inuit people in some regions show unexpectedly high levels of exposure, possibly through handling and consumption of Arctic wildlife. Free-ranging caribou (Rangifer tarandus are widely harvested for food across the Canadian North, show evidence of seroexposure to T. gondii, and are currently declining in numbers throughout the Arctic. We experimentally infected three captive reindeer (conspecific with caribou with 1000, 5000 or 10,000 oocysts of T. gondii via stomach intubation to assess clinical signs of infection, pathology, and tissue distribution. An unexposed reindeer served as a negative control. Signs of stress, aggression, and depression were noted for the first two weeks following infection. By 4 weeks post infection, all infected reindeer were positive on a modified agglutination test at the highest titer tested (1:200 for antibodies to T. gondii. At 20 weeks post infection, no gross abnormalities were observed on necropsy. Following histopathology and immunohistochemistry, tissue cysts were visualized in the reindeer given the highest and lowest dose of oocysts. Focal pleuritis and alveolitis were associated with respiratory problems in reindeer given the middle dose. DNA of T. gondii was detected following traditional DNA extraction and conventional PCR on 25 mg samples from 17/33 muscles and organs, and by magnetic capture DNA extraction from 100 g samples from all 26 tissues examined. This research demonstrated that reindeer/caribou can serve as intermediate hosts for T. gondii, and that the parasite may be associated with health effects in wildlife. The presence of T. gondii in all tissues tested, many of which are commonly consumed raw, smoked, or dried in northern communities, suggests that caribou may serve as a source of human exposure to T. gondii

Frequency of Toxoplasma gondii in the retina in eye banks in Brazil.

Science.gov (United States)

Costa, Deise F; Nascimento, Heloisa; Sutili, Aline; Nobrega, Fernando A J; Fowler, Flavio; Nobrega, Mario Junqueira; Garrido, Cristina; de Oliveira Dias, Janaina; Adán, Consuelo B D; Rizzo, Luiz Vicente; Silveira, Claudio; Belfort, Rubens; Commodaro, Alessandra G

2017-07-01

Ocular toxoplasmosis is the main cause of posterior uveitis worldwide frequently leading to vision loss. In Brazil, the seroprevalence of Toxoplasma gondii infection ranges from 50 to 80% depending of the region studied. The frequency of toxoplasmic retinal scar may reach 18% of the adults in the South of Brazil. Our goal was to determine the frequency of T. gondii DNA in retinas from eye banks from different regions in Brazil. A total of 162 eyes were obtained from eye banks in Manaus (n = 60), Sao Paulo (n = 60), Chapeco (n = 26), and Joinville (n = 16). The retinas were macroscopically analyzed and collected for DNA extraction. Real-time PCR (qPCR) was performed using the T. gondii B1 marker. By qPCR, a higher frequency of T. gondii DNA in the retinas from the eye bank of Joinville (25%) was found when compared to Manaus (5%). The retinas from Sao Paulo and Chapeco were qPCR negative. Clinical examination determined the retina lesions to be compatible with toxoplasmosis in the following frequencies: Joinville (62.5%), Manaus (10%), Sao Paulo (6.7%), and Chapeco (15.4%).

Lacrimal secretory IgA in active posterior uveitis induced by Toxoplasma gondii.

Science.gov (United States)

Lynch, Maria Isabel; Cordeiro, Francisco; Ferreira, Silvana; Ximenes, Ricardo; Oréfice, Fernando; Malagueño, Elizabeth

2004-12-01

It is quite difficult to diagnose active toxoplasmosis in patients with ocular toxoplasmosis. Active posterior uveitis presumably due to Toxoplasma gondii infection (APUPT) is seldom produced during a prime-infection; hence most patients do not show high IgM antibodies. High levels of IgA have been described in active toxoplasmosis. The purpose of this study was to investigate possible association between APUPT and the specific anti-parasite sIgA in tears. The study was carried out as case-control. Tears of 25 clinically confirmed APUPT patients and 50 healthy control subjects were analyzed. All were IgG seropositive. Specific sIgA was determined by ELISA assay using T. gondii RH strain crude extract. Anti-T. gondii sIgA was found in 84% of the cases and in 22% of the control subjects. The intensity of the reaction was higher in APUPT cases (P = 0.007). There was strong association between APUPT patients and lacrimal sIgA (odds-ratio 18.61, P = 0.0001). ELISA test sensitivity was 84% and specificity 78%. Our data suggest that anti-T.gondii secretory IgA found in tears may become an important marker for active ocular toxoplasmosis.

Aborto espontâneo e toxoplasmose ocular em um casal infectado com Toxoplasma gondii = Spontaneous abortion and ocular toxoplasmosis in a couple infected with Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Souza, Carla Zangari de

2015-01-01

Full Text Available Objetivos: Relatar os casos de um casal, em que a esposa apresentou toxoplasmose na gestação e o esposo, após 15 anos, foi diagnosticado com toxoplasmose ocular. Relato dos casos: Gestante, grávida de gêmeos, residente de um estado na região Sul do Brasil. No primeiro mês de gestação apresentou sorologia não reagente para IgG e IgM anti-Toxoplasma gondii. Na sétima semana de gestação houve soroconversão (IgM e IgG anti-T. gondii reagentes e aborto natural. O esposo, após 15 anos desde o episódio da esposa, queixou-se de visão embaçada/irritada. O exame de fundoscopia revelou lesões típicas de coriorretinite recidivante por toxoplasmose no olho direito. Os exames sorológicos foram IgG anti-T. gondii reagente e IgM anti-T. gondii não reagente. Conclusões: Este relato, de um casal com desfechos clínicos importantes de toxoplasmose, em diferentes formas, enfatiza a relevância do problema da toxoplasmose, que nas suas diversas manifestações, pode trazer graves consequências para a vida de uma família

toxoMine: an integrated omics data warehouse for Toxoplasma gondii systems biology research.

Science.gov (United States)

Rhee, David B; Croken, Matthew McKnight; Shieh, Kevin R; Sullivan, Julie; Micklem, Gos; Kim, Kami; Golden, Aaron

2015-01-01

Toxoplasma gondii (T. gondii) is an obligate intracellular parasite that must monitor for changes in the host environment and respond accordingly; however, it is still not fully known which genetic or epigenetic factors are involved in regulating virulence traits of T. gondii. There are on-going efforts to elucidate the mechanisms regulating the stage transition process via the application of high-throughput epigenomics, genomics and proteomics techniques. Given the range of experimental conditions and the typical yield from such high-throughput techniques, a new challenge arises: how to effectively collect, organize and disseminate the generated data for subsequent data analysis. Here, we describe toxoMine, which provides a powerful interface to support sophisticated integrative exploration of high-throughput experimental data and metadata, providing researchers with a more tractable means toward understanding how genetic and/or epigenetic factors play a coordinated role in determining pathogenicity of T. gondii. As a data warehouse, toxoMine allows integration of high-throughput data sets with public T. gondii data. toxoMine is also able to execute complex queries involving multiple data sets with straightforward user interaction. Furthermore, toxoMine allows users to define their own parameters during the search process that gives users near-limitless search and query capabilities. The interoperability feature also allows users to query and examine data available in other InterMine systems, which would effectively augment the search scope beyond what is available to toxoMine. toxoMine complements the major community database ToxoDB by providing a data warehouse that enables more extensive integrative studies for T. gondii. Given all these factors, we believe it will become an indispensable resource to the greater infectious disease research community. © The Author(s) 2015. Published by Oxford University Press.

Seroepidemiology of Toxoplasma gondii infection in bats from São Paulo city, Brazil

Science.gov (United States)

Toxoplasmosis is a parasitic zoonosis caused by Toxoplasma gondii with a worldwide distribution. The aim of this study was to determine the frequency of IgG anti-T. gondii antibodies in bats from São Paulo city, Brazil. A total of 616 serum samples were collected from 22 species of bats. Anti-T. gon...

Transplacental transmission of Toxoplasma gondii in minipigs infected with strains of different virulence

DEFF Research Database (Denmark)

Jungersen, Gregers; Bille-Hansen, Vivi; Jensen, Lene Bai

2001-01-01

Infections with the Zoonotic protozoan Toxoplasma gondii during pregnancy can result in severe fetal infections. To investigate the use of pigs as animal models for congenital toxoplasmosis, tachyzoites of 5 T. gondii strains, with low to intermediate virulence in mice, were intravenously...... animal models fur studies of transplacental transmission and pathogenesis of congenital toxoplasmosis....

Lack of Association Between Toxoplasma gondii Infection and Diabetes Mellitus: A Matched Case-Control Study in a Mexican Population.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Loera-Moncivais, Nayely; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Hernandez-Madrid, Guillermina; Rabago-Sanchez, Elizabeth; Centeno-Tinoco, Maria Magdalena; Sandoval-Carrillo, Ada A; Salas-Pacheco, Jose M; Campos-Moreno, Oscar Vladimir; Antuna-Salcido, Elizabeth Irasema

2017-06-01

Very little is known about the association between infection with Toxoplasma gondii ( T. gondii ) and diabetes mellitus. We perform an age- and gender-matched case-control study to determine the association of T. gondii infection and diabetes mellitus. Cases included 156 patients with diabetes mellitus and 156 controls without diabetes mellitus who attended in two public clinics in Durango City, Mexico. Sera of cases and controls were tested for the presence of anti- Toxoplasma IgG and IgM antibodies using commercially available enzyme-linked fluorescence assays (ELFA). Anti- T. gondii IgG antibodies were found in 10 (6.4%) of the 156 cases and in five (3.2%) of the 156 controls (odds ratio (OR): 2.06; 95% confidence interval (CI): 0.69 - 6.19; P = 0.18). The frequency of high (> 150 IU/mL) anti- T. gondii IgG levels in seropositive cases (1/10: 10.0%) was comparable to the one (1/5: 20%) in seropositive controls (OR: 0.44; 95% CI: 0.02 - 9.03; P = 1.00). None of the 10 cases and five controls with seropositivity to anti- T. gondii IgG antibodies were positive for anti- T. gondii IgM antibodies. Stratification by gender showed similar frequencies of T. gondii infection in female cases (7/107: 6.5%) and female controls (4/107: 3.7%) (OR: 1.80; 95% CI: 0.51 - 6.34; P = 0.53), and in male cases (3/49: 6.1%) and male controls (1/49: 2.0%) (OR: 3.13; 95% CI: 0.31 - 31.19; P = 0.61). We conclude that there is not serological evidence of an association between T. gondii infection and diabetes mellitus in the studied subjects in Durango City, Mexico. Further studies to elucidate the role of T. gondii in diabetes should be conducted.

Antibody reaction of human anti-Toxoplasma gondii positive and negative sera with Neospora caninum antigens

OpenAIRE

Nam, Ho-Woo; Kang, Seung-Won; Choi, Won-Young

1998-01-01

Anti-Neospora caninum antibody was detected in anti-Toxoplasma gondii positive and negative human sera by ELISA, western blot and immunofluorescence assay (IFA). Twelve cases out of 172 (6.7%) Toxoplasma-positive sera cross-reacted with both T. gondii and N. caninum antigens, and one out of 110 Toxoplasma-negative sera reacted with N. caninum antigen by ELISA. By western blot, all 12 sera reacted with T. gondii antigens with various banding patterns but specifically at 30 kDa (SAG1) and 22 kD...

A comparative study of small RNAs in Toxoplasma gondii of distinct genotypes

Directory of Open Access Journals (Sweden)

Wang Jielin

2012-09-01

Full Text Available Abstract Background Toxoplasma gondii is an intracellular parasite with a significant impact on human health. Inside the mammalian and avian hosts, the parasite can undergo rapid development or remain inactive in the cysts. The mechanism that regulates parasite proliferation has not been fully understood. Small noncoding RNAs (sncRNA such as microRNAs (miRNAs are endogenous regulatory factors that can modulate cell differentiation and development. It is anticipated that hundreds of miRNAs regulate the expression of thousands of genes in a single organism. SncRNAs have been identified in T. gondii, however the profiles of sncRNAs expression and their potential regulatory function in parasites of distinct genotypes has largely been unknown. Methods The transcription profiles of miRNAs in the two genetically distinct strains, RH and ME49, of T. gondii were investigated and compared by a high-through-put RNA sequencing technique and systematic bioinformatics analysis. The expression of some of the miRNAs was confirmed by Northern blot analysis. Results 1,083,320 unique sequences were obtained. Of which, 17 conserved miRNAs related to 2 metazoan miRNA families and 339 novel miRNAs were identified. A total of 175 miRNAs showed strain-specific expression, of which 155 miRNAs were up-regulated in RH strain and 20 miRNAs were up-regulated in ME49 strain. Strain-specific expression of miRNAs in T. gondii could be due to activation of specific genes at different genomic loci or due to arm-switching of the same pre-miRNA duplex. Conclusions Evidence for the differential expression of miRNAs in the two genetically distinct strains of T. gondii has been identified and defined. MiRNAs of T. gondii are more species-specific as compared to other organisms, which can be developed as diagnostic biomarkers for toxoplasmosis. The data also provide a framework for future studies on RNAi-dependent regulatory mechanisms in the zoonotic parasite.

Screening of chemical compound libraries identified new anti-Toxoplasma gondii agents.

Science.gov (United States)

Adeyemi, Oluyomi Stephen; Sugi, Tatsuki; Han, Yongmei; Kato, Kentaro

2018-02-01

Toxoplasma gondii is the etiological agent of toxoplasmosis, a common parasitic disease that affects nearly one-third of the human population. The primary infection can be asymptomatic in healthy individuals but may prove fatal in immunocompromised individuals. Available treatment options for toxoplasmosis patients are limited, underscoring the urgent need to identify and develop new therapies. Non-biased screening of libraries of chemical compounds including the repurposing of well-characterized compounds is emerging as viable approach to achieving this goal. In the present investigation, we screened libraries of natural product and FDA-approved compounds to identify those that inhibited T. gondii growth. We identified 32 new compounds that potently inhibit T. gondii growth. Our findings are new and promising, and further strengthen the prospects of drug repurposing as well as the screening of a wide range of chemical compounds as a viable source of alternative anti-parasitic therapeutic agents.

First isolation and genotyping of Toxoplasma gondii from bats (Mammalia: Chiroptera).

Science.gov (United States)

Cabral, A D; Gama, A R; Sodré, M M; Savani, E S M M; Galvão-Dias, M A; Jordão, L R; Maeda, M M; Yai, L E O; Gennari, S M; Pena, H F J

2013-03-31

There are currently no reports on the isolation and molecular examination of Toxoplasma gondii from bats. Here, we report the isolation and genotypic characterisation of two T. gondii isolates from bats. A total of 369 bats from different municipalities in São Paulo state, southeastern Brazil, were captured and euthanised, and collected tissues (heart and pectoral muscle) were processed for each bat or in pools of two or three bats and bioassayed in mice (a total of 283 bioassays). Eleven PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) markers were used to genotype positive samples: SAG1, SAG2 (5'-3'SAG2 and alt. SAG2), SAG3, BTUB, GRA6, L358, c22-8, c29-2, PK1, CS3 and Apico. The parasite was isolated from two bats from São Paulo city: an insectivorous bat, the velvety free-tailed bat Molossus molossus, and a hematophagous bat, the common vampire bat Desmodus rotundus. Isolates were designated TgBatBr1 and TgBatBr2, respectively. The genotype of the isolate from M. molossus (TgBatBr1) has been previously described in an isolate from a capybara from São Paulo state, and the genotype from the D. rotundus isolate (TgBatBr2) has already been identified in isolates from cats, chickens, capybaras, sheep, a rodent and a common rabbit from different Brazilian states, suggesting that this may be a common T. gondii lineage circulating in some Brazilian regions. Isolation of T. gondii from a hematophagous species is striking. This study reveals that bats can share the same isolates that are found in domesticated and wild terrestrial animals. This is the first report of the isolation and genotyping of T. gondii in chiropterans. Copyright © 2012 Elsevier B.V. All rights reserved.

Neospora caninum and Toxoplasma gondii antibody prevalence in Alaska wildlife.

Science.gov (United States)

Stieve, Erica; Beckmen, Kimberlee; Kania, Stephen A; Widner, Amanda; Patton, Sharon

2010-04-01

Free-ranging caribou and moose populations in some regions of Alaska undergo periodic declines in numbers. Caribou and moose are managed by the state as valuable resources for not only sustenance and subsistence, but also for cultural heritage. Incidence and prevalence of diseases that may impact herd health and recruitment from year to year are relevant to management decisions aimed to protect the long-term viability of these herds. Neospora caninum and Toxoplasma gondii are two apicomplexan parasites that can cause neurologic disease and abortions in their intermediate hosts and less frequently cause disease in their definitive hosts. The definitive hosts of N. caninum and T. gondii are canids and felids, respectively, and prevalence in the environment is in part dependent on maintenance of the life cycle through the definitive hosts. Serum samples from caribou (Rangifer tarandus, n=453), wolf (Canis lupus, n=324), moose (Alces alces, n=201), black-tailed deer (Odocoileus hemionus, n=55), coyote (Canis latrans, n=12), and fox (Vulpes vulpes, n=9) collected in Alaska were assayed for N. caninum- and T. gondii-reactive antibodies with an immunofluorescent antibody test (IFAT) and a modified agglutination test (MAT), respectively. Seroprevalence of N. caninum was greater in caribou (11.5%) than in wolves (9.0%), moose (0.5%), or black-tailed deer (0%). Seroprevalence of T. gondii was greater in wolves (17.8%) than in caribou (0.4%), moose (0%), or black-tailed deer (0%). Seroprevalence of N. caninum and T. gondii were 16.7% and 0.0% in coyotes and 0.0% and 12.5% in fox, but small sample sizes prevented further analysis. Antibodies to N. caninum in young caribou compared to adult caribou suggest that vertical transmission may be an important component of new infections in Alaskan caribou. The spatial distribution of antibody-positive individuals across Alaska may reflect differences in frequency of definitive hosts and alteration of predation patterns among regions.

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...... almost exclusively on molecules which control the interaction of the parasite with the host cell. We show that some secreted invasion-related proteins and surface genes which are known to control virulence and host cell interactions in Toxoplasma are dramatically altered in their expression...... and functionality in Neospora and propose that evolution of these genes may underpin the ecological niches inhabited by coccidian parasites....

Sporulation and survival of Toxoplasma gondii oocysts in different types of commercial cat litters

Science.gov (United States)

Toxoplasma gondii oocysts are environmentally resistant and can survive outdoors for months in the dry and cold climates. In the present study, sporulation and survival of T. gondii oocysts was studied in different types of cat litters commercially available in the US. Oocysts sporulated within 2-...

Impaired chromatin remodelling at STAT1-regulated promoters leads to global unresponsiveness of Toxoplasma gondii-infected macrophages to IFN-γ.

Directory of Open Access Journals (Sweden)

Christine Lang

2012-01-01

Full Text Available Intracellular pathogens including the apicomplexan and opportunistic parasite Toxoplasma gondii profoundly modify their host cells in order to establish infection. We have shown previously that intracellular T. gondii inhibit up-regulation of regulatory and effector functions in murine macrophages (MΦ stimulated with interferon (IFN-γ, which is the cytokine crucial for controlling the parasites' replication. Using genome-wide transcriptome analysis we show herein that infection with T. gondii leads to global unresponsiveness of murine macrophages to IFN-γ. More than 61% and 89% of the transcripts, which were induced or repressed by IFN-γ in non-infected MΦ, respectively, were not altered after stimulation of T. gondii-infected cells with IFN-γ. These genes are involved in a variety of biological processes, which are mostly but not exclusively related to immune responses. Analyses of the underlying mechanisms revealed that IFN-γ-triggered nuclear translocation of STAT1 still occurred in Toxoplasma-infected MΦ. However, STAT1 bound aberrantly to oligonucleotides containing the IFN-γ-responsive gamma-activated site (GAS consensus sequence. Conversely, IFN-γ did not induce formation of active GAS-STAT1 complexes in nuclear extracts from infected MΦ. Mass spectrometry of protein complexes bound to GAS oligonucleotides showed that T. gondii-infected MΦ are unable to recruit non-muscle actin to IFN-γ-responsive DNA sequences, which appeared to be independent of stimulation with IFN-γ and of STAT1 binding. IFN-γ-induced recruitment of BRG-1 and acetylation of core histones at the IFN-γ-regulated CIITA promoter IV, but not β-actin was diminished by >90% in Toxoplasma-infected MΦ as compared to non-infected control cells. Remarkably, treatment with histone deacetylase inhibitors restored the ability of infected macrophages to express the IFN-γ regulated genes H2-A/E and CIITA. Taken together, these results indicate that Toxoplasma

Toxoplasmosis in dogs: first report of Toxoplasma gondii infection in any animal species in Angola.

Science.gov (United States)

Lopes, Ana Patrícia; Granada, Sara; Oliveira, Ana Cristina; Brancal, Hugo; Dubey, Jitender P; Cardoso, Luís; Vilhena, Hugo

2014-10-01

Despite the worldwide importance of zoonotic parasite Toxoplasma gondii, nothing is known of toxoplasmosis in animals in Angola. The present study aimed at estimating the seroprevalence and also at assessing correlates of T. gondii infection in pet dogs from Luanda, Angola. Dogs (n = 103) brought to a veterinary clinic in the city of Luanda were investigated. Serum samples were tested for antibodies to T. gondii with a modified agglutination test (MAT) commercial kit, at serial dilutions of 1∶20 to 1∶160. In accordance with the established cutoff value (MAT ≧20), 16 dogs [15·5%; 95% confidence interval (CI): 9·2-24·0%] had antibodies to T. gondii: 10 had a titer of 20, two had a titer of 40, and four had a titer of 80. Age (≧12 months) was found to be a risk factor for infection [odds ratio (OR) = 9·23; 95% CI: 1·16-73·27). For each 1-year increase in age, the risk of a dog being found seropositive significantly increased by an OR of 1·18 (95% CI: 1·02-1·36). The present study, which represents the first serological survey of T. gondii in any animal species from Angola, reveals a 15·5% seroprevalence of infection in pet dogs in Luanda. Further studies are needed to better understand the epidemiology of zoonotic T. gondii infection in Luanda and also in Angola.

Occurrence of Toxoplasma gondii antibodies in lowland tapirs maintained ex situ in Brazil and Paraguay

Directory of Open Access Journals (Sweden)

Maria Fernanda Naegeli Gondim

Full Text Available ABSTRACT: Lowland Tapir ( Tapirus terrestris is the second largest South American land mammal. It is strictly herbivorous and its exposure to Toxoplasma gondii should be indicative of environmental contamination by oocysts.In the present study antibodies to T. gondii in 47 Brazilian tapirs maintained ex situ in 10 Brazilian and in one Paraguayan institution were sought in serum samples by the modified agglutination test (MAT ≥25. None of the animals presented clinical signs during the study. From 47 animals 35 (74.5% were positive with titers of 25 in 8, 50 in 6, 100 in 12, 200 in 5, 400 in 1 and 800 in 3. One animal had samples collected on twice, and 19 were born in captivity. There was no association between occurrence of T. gondii antibodies and gender, and positive animals were reported in all institutions. The high occurrence of seropositive tapirs born ininstitutions (54.3% confirmed the high exposure of these mammals to T. gondii in captivity. Only two cases ofabortion were reported, but it was not possible to correlate these abortions to T. gondii infection.

Cytomegalovirus and Toxoplasma gondii seroprevalence in a Brazilian liver transplant waiting

Directory of Open Access Journals (Sweden)

R. A. M. B. Almeida

2007-01-01

Full Text Available Cytomegalovirus (CMV disease is a major cause of morbidity and mortality in solid organ transplantation. Disseminated toxoplasmosis after liver transplantation is a rare but fatal event. Serologic screening of the donor and the recipient is essential to prophylactic management, early diagnosis and therapeutic strategies to minimize the consequences of these infections. The aim of the present study was to determine the seroprevalence of CMV and Toxoplasma gondii (TG in a Brazilian liver transplant waiting list (LTWL. Serological data were collected from 44 candidates on the LTWL between May 2003 and November 2004. Serological investigation of antibodies IgM and IgG against CMV (anti-CMV and TG (anti-T. gondii was performed using fluorometry commercial kits. IgG anti-CMV was positive in 37 patients (94.9% out of 39 available results. There were not IgM anti-CMV positive results. Out of 36 analyzed patients, 22 (61.1% presented positive IgG anti-T. gondii and none had positive IgM anti-T. gondii. The high CMV seroprevalence among our LTWL reinforces the need for appropriate protocols to avoid related complications, like reactivation and superinfection by CMV. Environmental and drug prophylactic strategies against primary infection and reactivation, as well as early diagnosis and treatment of toxoplasmosis complications, are essential for the good outcome of transplant patients.

Detecção de anticorpos anti-Toxoplasma gondii em suínos criados e abatidos no Estado da Bahia, Brasil Detection anti-Toxoplasma gondii antibodies in swines bred and abated in the Bahia State, Brazil

Directory of Open Access Journals (Sweden)

Rodrigo A. Bezerra

2009-09-01

Full Text Available Objetivou-se verificar a ocorrência de anticorpos anti-Toxoplasma gondii em suínos criados e abatidos no Estado da Bahia. Foram coletadas e examinadas 465 amostras de sangue de suínos provenientes de criações de diferentes locais desse estado. Para a pesquisa de anticorpos anti-T. gondii, foi utilizada a técnica de Imunoadsorção Enzimática (ELISA e considerados positivos todos os animais com títulos iguais ou maiores que 1:16. Desses, 18,27% (85/465 foram positivos para anticorpos anti-T. gondii, sendo 30,76% (24/78 em Ilhéus, 18,10% (21/116 em Itabuna e 14,76% (40/271 em Simões Filho. Foram observadas diferenças significativas quanto ao sexo dos animais (p = 0,0171, ao sistema de criação (p = 0,0002 e à procedência dos animais (p = 0,0278 no município de Itabuna. Anticorpos anti-T. gondii foram encontrados nos animais estudados, podendo ser estes animais fonte de infecção para a população humana local.This study was performed to verify the occurrence of anti-Toxoplasma gondii antibodies in swine raised and slaughtered in the state of Bahia, Brazil. Four hundred sixty five swine blood samples from farms of different cities had been collected and examined. Anti-T. gondii antibodies was detected by the enzyme-linked immunosorbent assay (ELISA and considered positive all the animals with equal or bigger headings than 1:16. From these, 18.27% (85/465 of total sample were positive for T. gondii, 30.76% (24 in Ilhéus, 18.10% (21/116 in Itabuna and 14.76% (40/271 in Simões Filho. Significant differences were observed regarding animal sex (p = 0.0171, raising system (p = 0.0002 and origin of the animals (p = 0.0278 in the city of Itabuna. The occurrence of anti-T. gondii antibodies shows that swine can be a source of infection for the local human population.

Genotyping of samples from German patients with ocular, cerebral and systemic toxoplasmosis reveals a predominance of Toxoplasma gondii type II.

Science.gov (United States)

Herrmann, Daland C; Maksimov, Pavlo; Hotop, Andrea; Groß, Uwe; Däubener, Walter; Liesenfeld, Oliver; Pleyer, Uwe; Conraths, Franz J; Schares, Gereon

2014-10-01

Toxoplasmosis is an important zoonosis transmitted from animals to humans world-wide. In order to determine Toxoplasma gondii genotypes in individuals living in Germany and to compare findings with those in animals, we analysed nine independent and unlinked genetic markers (nSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) by PCR-RFLP in 83 archived T. gondii-positive DNA samples from patients with ocular toxoplasmosis (n=35), toxoplasmic encephalitis (n=32), systemic toxoplasmosis after bone-marrow transplantation (n=15) and congenital toxoplasmosis (n=1). In 46 of these 83 samples the presence of T. gondii DNA was confirmed by conventional end-point PCR. Among these, 17 T. gondii-positive samples were typed at all nine loci. The majority (15/17, 88.2%) of these samples were of T. gondii type II (i.e., including both, the Apico type II and Apico type I variants). In addition, in one sample a T. gondii type II/type III allele combination and in another sample a T. gondii genotype displaying type III alleles at all markers was observed. In the remaining 11 samples, in which T. gondii could only be partially typed, exclusively type II (n=10) or type III (n=1) alleles were observed. Results of the present study suggest that the majority of patients in Germany are infected with type II T. gondii regardless of the clinical manifestation of toxoplasmosis. This finding is in accord with the predominance of type II T. gondii in oocysts isolated from cats and in tissues of other intermediate hosts in Germany. Copyright © 2014 Elsevier GmbH. All rights reserved.

[The seroprevalence of Toxoplasma gondii in women from Sanliurfa, a province with a high raw meatball consumption].

Science.gov (United States)

Tekay, Fikret; Ozbek, Erdal

2007-01-01

Toxoplasma gondii is an obligate intracellular protozoan that can infect all kind of birds and all mammals including humans and is common throughout the world. The prevalence varies according to social and cultural habits, pet cats in homes and geographic factors. Domestic cats are considered to be an important source of Toxoplasma gondii infection. From January to June 2006, the prevalence of toxoplasmosis was retrospectively monitored from blood samples that had been sent to our laboratory in order to determine the levels of IgM and IgG. All the subjects were women and 2,586 blood samples were investigated with the chemiluminescence immunoassay method. The rates of Toxoplasma gondii IgM antibodies were found to be 3.0% (78/2,586) and that of Toxoplasma gondii IgG antibodies, 69.5% (1.798/2,586). The total rate of positivity of Toxoplasma gondii antibodies was 69.6% (1,801/2,586) and the negativity, 30.4% (785/2,586). The highest positive rates have been reported in the southeastern region of Turkey and the 69.6% detected in our study seems to be the highest rate. Raw meatball consumption is common in our region and raw meat has a high risk of Toxoplasma gondii infection by direct ingestion of tissue cysts. As a result we consider that the high frequency of Toxoplasma gondii seropositivity in this region is due to raw meatball consumption.

The neurotropic parasite Toxoplasma gondii increases dopamine metabolism.

Directory of Open Access Journals (Sweden)

Emese Prandovszky

Full Text Available The highly prevalent parasite Toxoplasma gondii manipulates its host's behavior. In infected rodents, the behavioral changes increase the likelihood that the parasite will be transmitted back to its definitive cat host, an essential step in completion of the parasite's life cycle. The mechanism(s responsible for behavioral changes in the host is unknown but two lines of published evidence suggest that the parasite alters neurotransmitter signal transduction: the disruption of the parasite-induced behavioral changes with medications used to treat psychiatric disease (specifically dopamine antagonists and identification of a tyrosine hydroxylase encoded in the parasite genome. In this study, infection of mammalian dopaminergic cells with T. gondii enhanced the levels of K+-induced release of dopamine several-fold, with a direct correlation between the number of infected cells and the quantity of dopamine released. Immunostaining brain sections of infected mice with dopamine antibody showed intense staining of encysted parasites. Based on these analyses, T. gondii orchestrates a significant increase in dopamine metabolism in neural cells. Tyrosine hydroxylase, the rate-limiting enzyme for dopamine synthesis, was also found in intracellular tissue cysts in brain tissue with antibodies specific for the parasite-encoded tyrosine hydroxylase. These observations provide a mechanism for parasite-induced behavioral changes. The observed effects on dopamine metabolism could also be relevant in interpreting reports of psychobehavioral changes in toxoplasmosis-infected humans.

Toxoplasma gondii seroprevalence in free-ranging moose (Alces alces) hunted for human consumption in Estonia

DEFF Research Database (Denmark)

Remes, Noora; Kärssin, Age; Must, Kärt

2018-01-01

In Estonia, northeastern Europe, antibodies against Toxoplasma gondii are common in many host species, including wildlife, domestic animals, and humans. Our nationwide study aimed to estimate T. gondii seroprevalence and its geographical distribution, and to evaluate plausible risk factors for se...

Mechanics of the Toxoplasma gondii oocyst wall

Science.gov (United States)

The ability of microorganisms to survive under extreme conditions is closely related to the physicochemical properties of their wall. In the ubiquitous protozoan parasite Toxoplasma gondii, the oocyst stage possesses a bilayered wall that protects the dormant but potentially infective parasites from...

Diagnosis of pulmonary infection with Toxoplasma gondii in immunocompromised HIV-positive patients by real-time PCR

DEFF Research Database (Denmark)

Petersen, E.; Edvinsson, B.; Lundgren, Bettina

2006-01-01

. In positive samples, the genotype of the parasite was determined by sequence analysis of the GRA6 gene. Positive results were achieved for 2% (7/332) of the samples tested. Genotyping was possible in two samples and revealed GRA6 type II T. gondii. PCR for detecting T. gondii in BAL samples should...... be performed in all immunosuppressed HIV-positive patients with symptoms of a systemic infection of unknown etiology. Trimethoprim-sulfamethoxazole prophylaxis does not exclude concomitant infection with T. gondii....

Lacrimal secretory IgA in active posterior uveitis induced by Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Maria Isabel Lynch

2004-12-01

Full Text Available It is quite difficult to diagnose active toxoplasmosis in patients with ocular toxoplasmosis. Active posterior uveitis presumably due to Toxoplasma gondii infection (APUPT is seldom produced during a prime-infection; hence most patients do not show high IgM antibodies. High levels of IgA have been described in active toxoplasmosis. The purpose of this study was to investigate possible association between APUPT and the specific anti-parasite sIgA in tears. The study was carried out as case-control. Tears of 25 clinically confirmed APUPT patients and 50 healthy control subjects were analyzed. All were IgG seropositive. Specific sIgA was determined by ELISA assay using T. gondii RH strain crude extract. Anti-T. gondii sIgA was found in 84% of the cases and in 22% of the control subjects. The intensity of the reaction was higher in APUPT cases (P = 0.007. There was strong association between APUPT patients and lacrimal sIgA (odds-ratio 18.61, P = 0.0001. ELISA test sensitivity was 84% and specificity 78% . Our data suggest that anti-T.gondii secretory IgA found in tears may become an important marker for active ocular toxoplasmosis.

Toxoplasma gondii seroprevalence and genotype diversity in select wildlife species from the southeastern United States

Directory of Open Access Journals (Sweden)

Richard W. Gerhold

2017-10-01

Full Text Available Abstract Background Toxoplasma gondii is a widespread protozoan parasite that infects humans and other animals. Previous studies indicate some genotypes of T. gondii are more frequently isolated in wildlife than agricultural animals, suggesting a wild/feral animal diversity model. To determine seroprevalence and genetic diversity of T. gondii in southeastern US wildlife, we collected sera from 471 wild animals, including 453 mammals and 18 birds, between 2011 and 2014. These serum samples were assayed for T. gondii infection using the modified agglutination test (MAT. Heart or tongue tissues from 66 seropositive animals were bioassayed in mice and 19 isolates were obtained. The isolated parasites were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP method employing 10 genetic markers. Results One hundred and ninety-six of 471 samples (41.6% had a titer ≥1:32 and were considered positive for T. gondii infection. Of 453 mammals, 195 (43% were seropositive, whereas only one (5.6% of 18 birds was seropositive. The seroprevalence in mammals was significantly higher than in the birds. Mammalian hosts with adequate samples size (≥ 20 comprised white-tailed deer (n = 241, feral hogs (n = 100, raccoons (n = 34 and coyotes (n = 22, with seroprevalences of 41.0%, 51.0%, 50.0% and 72.7%, respectively. Coyotes had significantly higher seroprevalence than the white-tailed deer. Genotyping revealed five distinct genotypes, including the ToxoDB PCR-RFLP genotype #5 (a.k.a type 12 for 15 isolates, genotype #3 (a.k.a. type II for 1 isolate, and genotypes #154, #167 and #216, each for 1 isolate. The results showed moderate to high infection rates of T. gondii in white-tailed deer, feral hogs, raccoons and coyotes. Genotyping results indicated limited genetic diversity and a dominance of genotype #5, which has been reported as a major type in wildlife in North America. Conclusions We conclude that T. gondii

Detection of Toxoplasma gondii DNA in horse meat from supermarkets in France and performance evaluation of two serological tests

Directory of Open Access Journals (Sweden)

Aroussi Abdelkrim

2015-01-01

Full Text Available In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT and enzyme-linked immunosorbent assay (ELISA in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended.

Detection of Toxoplasma gondii DNA in horse meat from supermarkets in France and performance evaluation of two serological tests.

Science.gov (United States)

Aroussi, Abdelkrim; Vignoles, Philippe; Dalmay, François; Wimel, Laurence; Dardé, Marie-Laure; Mercier, Aurélien; Ajzenberg, Daniel

2015-01-01

In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR) to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended. © A. Aroussi et al., published by EDP Sciences, 2015.

Toxoplasma gondii in experimentally infected Bos taurus and Bos indicus semen and tissues Toxoplasma gondii em semen e tecidos de Bos taurus and Bos indicus experimentalmente infectados

Directory of Open Access Journals (Sweden)

Leslie Scarpelli

2009-01-01

Full Text Available Eighteen young steers were inoculated with Toxoplasma gondii and randomly distributed into three groups of six animals each: GI, 2.5x10(5 "P" strain oocysts, GII, 5.0x10(6 "RH" strain tachyzoites, and GIII (Control. Clinical, serological and parasitemia exams were realized. Parasite investigation by bioassay and PCR was realized on semen and fragments of skeletal musculature, lymph nodes, brain, retina, spleen, liver, lung, testicle, epididymis and seminal vesicle. Blood and semen samples were collected on days -2, -1, 1, 3, 5, 7, 14 and weekly thereafter, up to postinfection day (PID 84. The inoculated steers (GI and GII presented hyperthermia from PID 3 to 16. Antibodies against T. gondii were detected through the indirect fluorescence antibody test (IFAT on PID 5 (1:16 in both inoculated groups (oocysts and tachyzoites, reaching peaks of 1:4096 on PID 7. Parasitemia outbursts occurred in all infected bovines, principally from PID 7 to 28, independent of the strain and inoculate used. Bioassays revealed the presence of parasites in semen samples of animals infected with oocysts (GI and tachyzoites (GII on several experimental days between PID 7 and 84. Tissue parasitism by T. gondii was diagnosed by bioassay and the PCR technique in several organ and tissue fragments. These findings suggest the possibility of sexual transmission of T. gondii in the bovine species.Dezoito bovinos foram inoculados com Toxoplasma gondii e distribuídos aleatoriamente em três grupos de seis bovinos cada: GI (2,5x10(5 oocistos da cepa "P", GII (5,0x10(6 taquizoítos da cepa "RH" e GIII (controle. Exames clínicos, sorológicos e parasitêmicos foram realizados. Pesquisas do parasito, por meio da bioprova e pela técnica de Reação em Cadeia pela Polimerase (PCR, foram realizadas no sêmen e em fragmentos de musculatura esquelética, linfonodos, cérebro, retina, baço, fígado, pulmão, testículo, epidídimo e vesícula seminal. Amostras de sangue e sêmen foram

Anticorpos contra Toxoplasma gondii em estudantes de medicina veterinária de Campo Grande, MS, Brasil Antibodies to Toxoplasma Gondii in veterinary medicine students of Campo Grande, MS, Brazil

Directory of Open Access Journals (Sweden)

Flábio Ribeiro de Araújo

2000-12-01

Full Text Available Amostras de soro obtidas de estudantes do curso de Medicina Veteriná ria da Universidade para o Desenvolvimento do Estado e da Região do Pantanal, Campo Grande, MS, Brasil, foram examinadas para a presença de anticorpos contra Toxoplasma gondii. Dos 145 soros testados, 44 (30,34% foram positivos na hemaglutinação, com título igual ou superior a 1:16. Não foram observadas associações entre as caracterí sticas epidemiológicas examinadas, tais como hábitos alimentares (ingestão de carne bovina crua ou malpassada, vegetais crus/não lavados, produtos lácteos não pasteurizados ou contato constante com cães e a presença de anticorpos contra T. gondii, exceto pelo percentual significativamente maior de estudantes soropositivos que relataram ter contato freqüente com gatos (P=0,03.Serum samples obtained from students of the School of Veterinary Medicine, Universidade para o Desenvolvimento do Estado e da Região do Pantanal, Campo Grande, MS, Brazil, were examined for Toxoplasma gondii gondii antibodies. Serum samples from 44 (30.34% of the 145 veterinary students examined were positive on the hemagglutination test, yielding a titer of 1:16 or greater. There were no relations between the epidemiological characteristics examined, such as food habits (eating of raw or rare-cooked cattle meat, raw/uncleaned vegetables, unpasteurized dairy products, frequent contact with dogs and the presence of T. gondii antibodies, except for a significantly higher percentual of seropositive students that reported frequent contact with cats (P=0.03.

Risk factors for acute Toxoplasma gondii diseases in Taiwan: a population-based case-control study.

Directory of Open Access Journals (Sweden)

Ting-Yi Chiang

Full Text Available Although human toxoplasmosis is a notifiable disease in Taiwan since 2007, little is known about its risk factors. This study aimed to investigate the risk factors for acute Toxoplasma gondii diseases in Taiwan. We conducted a nationwide population-based case-control study. Cases of acute human toxoplasmosis notified to the Taiwan Centers for Diseases Control (Taipei, Taiwan during 2008-2013 were compared with controls that were randomly selected from healthy T. gondii-seronegative blood donors who participated in a nationwide T. gondii seroepidemiologic study during 2009-2010. Cases and controls were matched according to age, gender and residency at an 1:8 ratio. Structured questionnaires were used to gather information regarding risk factors. A total of 30 laboratory-confirmed acute T. gondii disease cases and 224 controls were enrolled. The most common clinical manifestation of the cases was flu-like symptoms (n = 20, followed by central nervous system disease (n = 4, ocular diseases (n = 3, abortion (n = 2, and congenital infection (n = 1. Multivariate conditional logistic regression showed that raw clam consumption (adjusted odds ratio [OR] = 3.7; 95% confidence interval [CI] = 1.4-9.9 and having a cat in the household (adjusted OR = 2.9; 95% CI = 1.1-7.9 were two independent risk factors for acute T. gondii disease. We conclude that raw shellfish consumption and domestic cat exposure were risk factors for acquiring acute T. gondii diseases in Taiwan. This finding may guide future research and control policies.

Latent Toxoplasma gondii infection leads to improved action control.

Science.gov (United States)

Stock, Ann-Kathrin; Heintschel von Heinegg, Evelyn; Köhling, Hedda-Luise; Beste, Christian

2014-03-01

The parasite Toxoplasma gondii has been found to manipulate the behavior of its secondary hosts to increase its own dissemination which is commonly believed to be to the detriment of the host (manipulation hypothesis). The manipulation correlates with an up-regulation of dopaminergic neurotransmission. In humans, different pathologies have been associated with T. gondii infections but most latently infected humans do not seem to display overt impairments. Since a dopamine plus does not necessarily bear exclusively negative consequences in humans, we investigated potential positive consequences of latent toxoplasmosis (and the presumed boosting of dopaminergic neurotransmission) on human cognition and behavior. For this purpose, we focused on action cascading which has been shown to be modulated by dopamine. Based on behavioral and neurophysiological (EEG) data obtained by means of a stop-change paradigm, we were able to demonstrate that healthy young humans can actually benefit from latent T. gondii infection as regards their performance in this task (as indicated by faster response times and a smaller P3 component). The data shows that a latent infection which is assumed to affect the dopaminergic system can lead to paradoxical improvements of cognitive control processes in humans. Copyright © 2013 Elsevier Inc. All rights reserved.

Toxoplasma gondii seroprevalence in pet cats in Norway and risk factors for seropositivity.

Science.gov (United States)

Sævik, Bente Kristin; Krontveit, Randi Ingebjørg; Eggen, Kristine P; Malmberg, Nina; Thoresen, Stein I; Prestrud, Kristin W

2015-12-01

The aims of the study were to estimate Toxoplasma gondii seroprevalence in pet cats in Norway and to evaluate risk factors for seropositivity. Additionally, serum biochemistry and haematological variables for T gondii seropositive and seronegative cats were compared. A convenience sample of surplus sera submitted to the Central Laboratory, Norwegian University of Life Sciences, was collected. The samples were from healthy cats and cats with a variety of diseases. Analyses for IgG antibodies to T gondii were performed with a commercial direct agglutination test, with 1:40 as the threshold value. For risk factor analysis a logistic regression model of the relationship between predictors and the outcome was applied. One hundred and ninety-six of 478 cats were seropositive for T gondii, and the estimated seroprevalence in the study sample was 41.0% (95% confidence interval 36.6-45.4). Compared with domestic cats, pedigree cats had reduced risk for Toxoplasma seropositivity (odds ratio [OR] 0.42). Males had increased risk (OR 1.63) compared with females. The effect of age was highly significant, and an increase in the cats' age across the interquartile range (IQR; 52-160 months/4-13 years of age) doubled the risk of Toxoplasma seropositivity (OR 2.11). The risk for Toxoplasma seropositivity among cats living in Oslo was significantly reduced (OR 0.51) when compared with the rest of Norway. Pet cats in Norway appear to be commonly exposed to T gondii. Signalment and geographical region influenced the odds of Toxoplasma seropositivity, whereas health status did not. © ISFM and AAFP 2015.

Stray dogs as indicators of Toxoplasma gondii distributed in the environment: the first report across an urban-rural gradient in China

Directory of Open Access Journals (Sweden)

Yan Chao

2012-01-01

Full Text Available Abstract Background Toxoplasmosis is an important parasitic zoonosis caused by the protozoan Toxoplasma gondii that is distributed world-wide and infects a variety of hosts. However, the prevalence of T. gondii in the environment (such as soil, water and food is largely unknown. Due to the technical difficulty in oocyst counting directly, an alternative assay using the serologic status of T. gondii in free-living animals, such as stray or free-living dogs, as an indicator, can be used to evaluate environmental contamination indirectly, as they are exposed to the same risk of infection as humans and other animals. Results In the present study, 231 stray or free-living dogs across an urban-rural gradient were examined to assess the frequency of T. gondii in the environment. Specific antibodies to T. gondii were found in 93 dogs (40.3% by enzyme-linked immunosorbent assay (ELISA, and no statistically significant differences were observed in seroprevalences of T. gondii between urban dogs (38.7% and rural dogs (41% (p > 0.05. Conclusions A high seroprevalence of T. gondii in stray or free-living dogs in the present study indicates that there would be a wide distribution and a constant infection pressure of T. gondii across an urban-rural gradient, and the oocysts of T. gondii in the environment would be an important source of infection for humans and other animals both in urban and rural areas in China.

Presence of Toxoplasma gondii in Drinking Water from an Endemic Region in Southern Mexico.

Science.gov (United States)

Hernandez-Cortazar, Ivonne B; Acosta-Viana, Karla Y; Guzman-Marin, Eugenia; Ortega-Pacheco, Antonio; Segura-Correa, Jose C; Jimenez-Coello, Matilde

2017-05-01

Toxoplasmosis can be acquired through the ingestion of contaminated drinking water with oocysts of Toxoplasma gondii, highly resistant to the routinely disinfection processes; based on chlorination commonly used in the water supply industry. The aim of this study was to determine the presence of T. gondii DNA in samples of public drinking water from an endemic region of southern Mexico. In total 74 samples of water (5 L each) were collected from the three well fields (I, II, and III) and 71 independent wells, distributing public drinking water to the city of Merida Yucatan, after passing through the chlorination process. Water samples were filtered and concentrated by a sucrose solution, then DNA was extracted and evaluated through a nested-PCR (nPCR) specific for T. gondii. Positive samples were detected in 5.4% (4/74) of the water samples. This is the first report of the presence of T. gondii DNA in public drinking water from a large city in southern Mexico, where their consumption without any postpurification treatment could pose a risk for acquiring the infection in the urban population.

An experimental Toxoplasma gondii dose response challenge model to study therapeutic or vaccine efficacy in cats.

Directory of Open Access Journals (Sweden)

Jan B W J Cornelissen

Full Text Available High numbers of Toxoplasma gondii oocysts in the environment are a risk factor to humans. The environmental contamination might be reduced by vaccinating the definitive host, cats. An experimental challenge model is necessary to quantitatively assess the efficacy of a vaccine or drug treatment. Previous studies have indicated that bradyzoites are highly infectious for cats. To infect cats, tissue cysts were isolated from the brains of mice infected with oocysts of T. gondii M4 strain, and bradyzoites were released by pepsin digestion. Free bradyzoites were counted and graded doses (1000, 100, 50, 10, and 250 intact tissue cysts were inoculated orally into three cats each. Oocysts shed by these five groups of cats were collected from faeces by flotation techniques, counted microscopically and estimated by real time PCR. Additionally, the number of T. gondii in heart, tongue and brains were estimated, and serology for anti T. gondii antibodies was performed. A Beta-Poisson dose-response model was used to estimate the infectivity of single bradyzoites and linear regression was used to determine the relation between inoculated dose and numbers of oocyst shed. We found that real time PCR was more sensitive than microscopic detection of oocysts, and oocysts were detected by PCR in faeces of cats fed 10 bradyzoites but by microscopic examination. Real time PCR may only detect fragments of T. gondii DNA without the presence of oocysts in low doses. Prevalence of tissue cysts of T. gondii in tongue, heart and brains, and anti T. gondii antibody concentrations were all found to depend on the inoculated bradyzoite dose. The combination of the experimental challenge model and the dose response analysis provides a suitable reference for quantifying the potential reduction in human health risk due to a treatment of domestic cats by vaccination or by therapeutic drug application.

Infection of male rats with Toxoplasma gondii induces effort-aversion in a T-maze decision-making task.

Science.gov (United States)

Tan, Donna; Vyas, Ajai

2016-03-01

Rats chronically infected with protozoan Toxoplasma gondii exhibit greater delay aversion in an inter-temporal task. Moreover T. gondii infection also results in dendritic atrophy of basolateral amygdala neurons. Basolateral amygdala is reported to bias decision making towards greater effortful alternatives. In this context, we report that T. gondii increases effort aversion in infected male rats. This host-parasite association has been widely studied in the context of loss of innate fear in the infected males. It is suggested that reduced fear towards predators reflects a parasitic behavioral manipulation to enhance trophic transmission of T. gondii. Observations reported here extend this paradigm away from a monolithic change in fear and towards a multi-dimensional change in decision making. Copyright © 2016 Elsevier Inc. All rights reserved.

A seroepidemiological survey of Toxoplasma gondii infection in referred dogs to Veterinary Hospital of Ahvaz, Iran

Directory of Open Access Journals (Sweden)

Fatemeh Zarra-Nezhad

2017-12-01

Full Text Available Toxoplasma gondii is an intracellular protozoan parasite, which is the cause of toxoplasmosis and can infect a wide variety of warm-blooded animals, including dogs and humans. The present study evaluated the seroprevalence of T. gondii infection in pet dogs in Ahvaz, southwest city of Iran, and investigated the related possible risk factors. A total of 180 serum samples were collected from dogs referred to Veterinary Hospital of Ahvaz. The samples were then tested by indirect enzyme-linked immunosorbent assay. The prevalence of T. gondii antibodies were 46.67%. Logistic regression and chi square tests were used for evaluating of risk factors. The positivity increased statistically significantly with dog’s gender (56% females and 39% males, P = 0.001, age (18% in <2 years old, 96% in ≥4 years old, P = 0.001 and place of living (47% outdoor dogs 38% house hold dogs, P = 0.025. However, no statistically significant association was found with dogs’ breed, deworming, food ingestion or contact with cats. Overall, the results showed a relatively high seroprevalence of T. gondii infection in dogs in southwest Iran (Ahvaz and proved association of T. gondii prevalence rates with the dog’s age, gender and place of living. Keywords: Toxoplasma gondii, Toxoplasmosis, Indirect enzyme-linked immunosorbent assay, Outdoor dogs, House hold dogs, Deworming

Toxoplasmosis in dogs: First report of Toxoplasma gondii infection in any animal species in Angola

Science.gov (United States)

Despite the worldwide importance of zoonotic parasite Toxoplasma gondii nothing is known of toxoplasmosis in animals in Angola. The present study aimed at estimating the seroprevalence and also assessing correlates of T. gondii infection in pet dogs from Luanda, Angola. Dogs (n = 103) brought to a v...

Isolation of Viable Toxoplasma gondii from Tissues and Feces of Cats from Addis Ababa, Ethiopia

Science.gov (United States)

Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that excrete environmentally resistant oocysts in feces. In the present study, hearts, serum, and feces from 36 feral cats from Addis Ababa area, Ethiopia were examined for T. gondii infection. Antibodies to ...

Fatal toxoplasmosis in an immunosuppressed domestic cat from Brazil caused by Toxoplasma gondii clonal type I

Directory of Open Access Journals (Sweden)

Hilda Fátima de Jesus Pena

Full Text Available Abstract The objective of the study was to report on a fatal case of feline toxoplasmosis with coinfection with the feline leukemia virus (FeLV. A domestic cat (Felis silvestris catus presented intense dyspnea and died three days later. In the necropsy, the lungs were firm, without collapse and with many white areas; moderate lymphadenomegaly and splenomegaly were also observed. The histopathological examination showed severe necrotic interstitial bronchopneumonia and mild necrotic hepatitis, associated with intralesional cysts and tachyzoites of Toxoplasma gondii that were positive by anti-T. gondii immunohistochemical (IHC evaluation. The bone marrow showed chronic myeloid leukemia and the neoplastic cells were positive by anti-FeLV IHC evaluation. DNA extracted from lungs was positive for T. gondii by PCR targeting REP-529. T. gondii was characterized by PCR-RFLP and by the microsatellites technique. ToxoDB-PCR-RFLP #10, i.e. the archetypal type I, was identified. Microsatellite analysis showed that the strain was a variant of type I with two atypical alleles. This was the first time that a T. gondii clonal type I genotype was correlated with a case of acute toxoplasmosis in a host in Brazil.

Seroprevalence and Risk Factors Associated with Seropositivity to Toxoplasma gondii among Stray and Domestic Cats (Felis silvestris catus

Directory of Open Access Journals (Sweden)

Christel Bohn T. Garcia

2014-12-01

Full Text Available Toxoplasma gondii is a protozoan parasite that causes toxoplasmosis. It is widespread in the environment and infects a variety of warm-blooded animals, causing miscarriages and birth problems. Previous studies in the Philippines have determined the seropositivity of T. gondii in humans. However, the seroprevalence of the parasite among household pets, par ticularly its feline def initive host, remains insufficient . This study aimed to: (1 determine the seroprevalence of T. gondii antibodies among domestic and stray cats in the Philippines; and, (2 to analyze the risk factors associated with seropositivity. Blood samples from 59 domestic and stray cats were collected and tested for T. gondii seropositivity using a commercially available indirect ELISA kit, while pet owners and handlers were given questionnaires about their cats. Thirteen or 22.03% of the cats were seropositive to T. gondii, and risk factor analysis revealed a significant difference between domestic and stray cats with regard to diet (p = 0.026, OR = 8.333, c = 0.299 and domestication (p = 0.039, OR = 5.000, c = 0.276. Cats fed with table food tested 31.43% seropositive compared to the 4.35% of those fed with cat food, whereas 33.33% of the stray cats were seropositive compared to 7.69% for domestic cats. Odds ratio test showed that the risk factors studied were associated with higher likelihood of T. gondii seropositivity. These results implicate diet and environment in the transmission dynamics of T. gondii among cats.

Incidence of adult brain cancers is higher in countries where the protozoan parasite Toxoplasma gondii is common

OpenAIRE

Thomas, Frédéric; Lafferty, Kevin D.; Brodeur, Jacques; Elguero, Eric; Gauthier-Clerc, Michel; Missé, Dorothée

2011-01-01

We explored associations between the common protozoan parasite Toxoplasma gondii and brain cancers in human populations. We predicted that T. gondii could increase the risk of brain cancer because it is a long-lived parasite that encysts in the brain, where it provokes inflammation and inhibits apoptosis. We used a medical geography approach based on the national incidence of brain cancers and seroprevalence of T. gondii. We corrected reports of incidence for national gross domestic product b...

Isolation and characterization of new genetic types of toxoplasma gondii and prevalence of trichinella murrelli from black bear (Ursus americanus)

Science.gov (United States)

Black bears (Ursus americanus) are hosts for two important zoonotic parasites, Toxoplasma gondii and Trichinella spp. and bears are hunted for human consumption in the USA. Little is known of the genetic diversity of T. gondii circulating in wildlife. In the present study, antibodies to T. gondii we...

High prevalence and genotypes of Toxoplasma gondii isolated from goats, from a retail meat store, destined for human consumption in the USA.

Science.gov (United States)

Dubey, J P; Rajendran, C; Ferreira, L R; Martins, J; Kwok, O C H; Hill, D E; Villena, I; Zhou, H; Su, C; Jones, J L

2011-07-01

Little information is available concerning the presence of viable Toxoplasma gondii in tissues of goats worldwide. In the present study, hearts of 234 goats obtained from a local USA grocery store were examined for T. gondii infection. Blood clot or fluid removed from each heart was tested for antibodies to T. gondii by using the modified agglutination test (MAT). Antibodies to T. gondii were found in 125 (53.4%) of 234 goats, with titers of 1:5 in 20, 1:10 in 44, 1:20 in 16, 1:40 in five, 1:160 in five, 1:320 in five, and 1:640 or higher in 30 goats. Hearts of 112 goats (46 goats goats 1:10 or higher) were used for isolation of viable T. gondii by bioassays in mice. For bioassays, 50 g of the myocardium were digested in an acid pepsin solution and the digest inoculated into mice; the recipient mice were examined for T. gondii infection. Toxoplasma gondii was isolated from 29 goats; from hearts of one of 46 with titers of goat strains. Taken together, these results indicate high parasite prevalence and moderate genetic diversity of T. gondii in goats, which have important implications in public health. We believe this is the first genetic analysis of T. gondii isolates from goats in the USA. Published by Elsevier Ltd.

Seroprevalence and Risk Factors of Toxoplasma gondii Infection in Buffaloes, Sheep and Goats in Yunnan Province, Southwestern China

Directory of Open Access Journals (Sweden)

Fengcai ZOU

2015-12-01

Full Text Available Background: The seroprevalence of Toxoplasma gondii infection in buffaloes, sheep and goats in Yunnan Province, southwestern China was conducted between May 2012 and December 2013.Methods: A total of 973 (427 buffaloes, 154 sheep and 392 goats serum samples were collected from seven administrative regions of Yunnan Province, and exam­ined for T. gondii antibodies by indirect hemagglutination (IHA test. Some risk fac­tors related to species, age, gender and geographical origin were determined using a multinomial logistic regression.Results: The overall seroprevalence of T. gondii in ruminant species was estimated at 11.9%. The final logistic regression model demonstrated that host species and geographical origin were the main risk factors associated with T. gondii infection (P﹤0.05.Conclusion: Taken together, the results of the present study revealed a high expo­sure to T. gondii in ruminant species in Yunnan Province, which has an important implication for public health.

Toxoplasma gondii: 1908-2008, homage to Nicolle, Manceaux and Splendore

Directory of Open Access Journals (Sweden)

David J P Ferguson

2009-03-01

Full Text Available The discovery of Toxoplasma gondii independently by Nicolle and Manceaux (1908 and Splendore (1908 was to open a "Pandora's Box" that has led research on this parasite into a number of scientific disciplines. In the 100 years since its discovery, the mystery surrounding T. gondii and its inter-relationship with humans has continued to provide a stimulating source of material in many areas of research, resulting in the publication of almost 20,000 papers and a number of books. This flood of diverse information shows no sign of abating, with an average of 10 papers per week appearing in PubMed. Herein, it is impossible to do more than provide a very superficial comment on what has become a massive body of scientific information. T. gondii has many unique features and seems to be the "exception to almost every rule" thus acting as a focus for research in disciplines from epidemiology to immunology to human behaviour to cell biology to human disease. In this review a number of the historical advances will be mentioned and combined with a description of the basic biology of the parasite.

Toxoplasma gondii Infection and Mixed Anxiety and Depressive Disorder: A Case-Control Seroprevalence Study in Durango, Mexico.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Sanchez-Anguiano, Luis Francisco; Hernandez-Tinoco, Jesus; Berumen-Segovia, Luis Omar; Torres-Prieto, Yazmin Elizabeth; Estrada-Martinez, Sergio; Perez-Alamos, Alma Rosa; Ortiz-Jurado, Maria Nalleli; Molotla-de-Leon, Gabriel; Beristain Garcia, Isabel; Rabago-Sanchez, Elizabeth; Liesenfeld, Oliver

2016-07-01

The parasite Toxoplasma gondii (T. gondii) may invade the brain and might induce behavioral changes. We sought to determine the association of T. gondii infection and mixed anxiety and depressive disorder. Through an age- and gender-matched case-control seroprevalence study, we examined 65 patients suffering from mixed anxiety and depressive disorder (WHO ICD-10 code: F41.2) attending in a public hospital of mental health and 260 control subjects without this disorder from the general population. Sera of participants were analyzed for anti-Toxoplasma IgG and IgM antibodies using enzyme-linked immunoassays. Fifteen (23.1%) of the 65 patients and 18 (6.9%) of the 260 controls had anti-T. gondii IgG antibodies (odds ratio (OR): 4.03; 95% confidence interval (CI): 1.90 - 8.53; P 150 IU/mL) anti-T. gondii IgG levels was similar in cases and controls (OR: 0.25; 95% CI: 0.05 - 1.06; P = 0.05). Seroprevalence was similar in male cases and controls (P = 1.0); however, seroprevalence was significantly higher in female cases than in female controls (OR: 7.08; 95% CI: 2.83 - 17.67; P mixed anxiety and depressive disorder. Further research to confirm this association and to determine the seroepidemiology of T. gondii infection in patients with this disorder is needed.

Antibody Prevalence and Isolation of Viable Toxoplasma gondii from Raptors in the Southeastern USA.

Science.gov (United States)

Love, David; Kwok, Oliver C; Verma, Shiv Kumar; Dubey, Jitender P; Bellah, Jamie

2016-07-01

Raptors are good indicators of the prevalence of Toxoplasma gondii in the environment because they prey on small mammals and birds. These prey species are a major source of infection in domestic cats ( Felis catus ), which shed the environmentally resistant oocysts. We assessed T. gondii infection in 281 opportunistically available raptors at a rehabilitation facility between 2012 and 2014. Antibodies to T. gondii were assayed by a modified agglutination test (cutoff 1:25) and found in serum of 22/71 Red-tailed Hawks ( Buteo jamaicensis ), 25/54 Barred Owls ( Strix varia ), 9/41 Red-shouldered Hawks ( Buteo lineatus ), 13/28 Great Horned Owls ( Bubo virginianus ), 6/20 Broad-winged Hawks ( Buteo platypterus ), 2/16 Eastern Screech Owls (Megascops asio), 12/13 Bald Eagles ( Haliaeetus leucocephalus ), 6/12 Cooper's Hawks ( Accipiter cooperii ), 1/8 Black Vultures ( Coragyps atratus ), and 1/1 Golden Eagle ( Aquila chrysaetos ). Antibodies were not detected in 5 Barn Owls ( Tyto alba ), 3 American Kestrels ( Falco sparverius ), 1 Mississippi Kite ( Ictinia mississippiensis ), and 1 Osprey ( Pandion haliaetus ). Viable T. gondii was isolated from the tissues of 1 antibody-positive Barred Owl and identified as a strain having type II alleles at all 10 loci tested, except one (ToxoDB polymerase chain reaction-restriction fragment length polymorphism genotype 3). Type II strain is the most common strain in the US. Results of this study indicate a high prevalence of T. gondii in some raptor species and the first reported genotyping from a Barred Owl.

Comparison of three diagnostic methods for the detection of Toxoplasma gondii in free range chickens.

Science.gov (United States)

Hamidinejat, H; Nabavi, L; Mayahi, M; Ghourbanpoor, M; Pourmehdi Borojeni, M; Norollahi Fard, S; Shokrollahi, M

2014-09-01

Detection of Toxoplasma gondii in free range chickens is an indicator of the prevalence and distribution pattern of T. gondii in the environment. For this purpose, serologic assays especially modified agglutination test (MAT) is the main approach in the literature. The main goal of this study was to compare the polymerase chain reaction (PCR) based on amplification of first internal transcribed spacer (ITS-1) of ribosomal DNA gene, ELISA, and MAT to demonstrate T. gondii infection in free range chicken. A total of 106 adult free - range chickens were killed. Blood, whole heart and brain samples were taken. Sera were examined for the presence of T. gondii antibodies by ELISA and MAT as well. Selected tissues were used for PCR and bioassay in mice. The results revealed that 48.11%, 51.89%, 46.23% and 27.36% of chickens were positive in ELISA, MAT, PCR and bioassay in mice respectively. Good correlation between the results of PCR, ELISA and MAT were detected, but not with bioassay in mice. Compared with PCR, the sensitivity and specificity of ELISA were 92.16% and 96.36% respectively and also for MAT, the sensitivity was 81.81% and the specificity was 92.15%. The specific diagnosis of T. gondii infection in chickens is central to a better understanding of the epidemiology and dynamics of transmission among the various host population and is particularly important for planning effective optimal prevention and control programs. Our data in the present study demonstrated that PCR, ELISA and the MAT are helpful and precise methods to detect T. gondii in naturally infected free-range chickens.

First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico

OpenAIRE

Torres-Castro, M.; Noh-Pech, H.; Puerto-Hern?ndez, R.; Reyes-Hern?ndez, B.; Panti-May, A.; Hern?ndez-Betancourt, S.; Yeh-Gorocica, A.; Gonz?lez-Herrera, L.; Zavala-Castro, J.; Puerto, F.I.

2016-01-01

Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplic...

Seroprevalence of Toxoplasma gondii in free-ranging and feral cats on Amami Oshima Island, Japan.

Science.gov (United States)

Matsuu, Aya; Yokota, Shin-Ichi; Ito, Keiko; Masatani, Tatsunori

2017-11-17

On Amami Oshima Island, free-ranging and feral cats are harmful to wildlife populations. In this study, the seroprevalence of Toxoplasma gondii in these cats was examined using a newly developed Gaussia luciferase immunoprecipitation system assay. Of 1,363 cats, 123 cats (9.0%) was positive for T. gondii. The prevalence was significantly different in different areas; among cats in the rural area, where many wild animals live, including endangered species, T. gondii infection was more prevalent than in the urban area of the island. This finding indicates a possible risk to wildlife of infection from free-ranging and feral cats. Therefore, management of cats is important for wildlife conservation.

Localisation of gluconeogenesis and tricarboxylic acid (TCA)-cycle enzymes and first functional analysis of the TCA cycle in Toxoplasma gondii.

Science.gov (United States)

Fleige, Tobias; Pfaff, Nils; Gross, Uwe; Bohne, Wolfgang

2008-08-01

The apicomplexan parasite Toxoplasma gondii displays some unusual localisations of carbohydrate converting enzymes, which is due to the presence of a vestigial, non-photosynthetic plastid, referred to as the apicoplast. It was recently demonstrated that the single pyruvate dehydrogenase complex (PDH) in T. gondii is exclusively localised inside the apicoplast but absent in the mitochondrion. This raises the question about expression, localisation and function of enzymes for the tricarboxylic acid (TCA)-cycle, which normally depends on PDH generated acetyl-CoA. Based on the expression and localisation of epitope-tagged fusion proteins, we show that all analysed TCA cycle enzymes are localised in the mitochondrion, including both isoforms of malate dehydrogenase. The absence of a cytosolic malate dehydrogenase suggests that a typical malate-aspartate shuttle for transfer of reduction equivalents is missing in T. gondii. We also localised various enzymes which catalyse the irreversible steps in gluconeogenesis to a cellular compartment and examined mRNA expression levels for gluconeogenesis and TCA cycle genes between tachyzoites and in vitro bradyzoites. In order to get functional information on the TCA cycle for the parasite energy metabolism, we created a conditional knock-out mutant for the succinyl-CoA synthetase. Disruption of the sixth step in the TCA cycle should leave the biosynthetic parts of the cycle intact, but prevent FADH2 production. The succinyl-CoA synthetase depletion mutant displayed a 30% reduction in growth rate, which could be restored by supplementation with 2 microM succinate in the tissue culture medium. The mitochondrial membrane potential in these parasites was found to be unaltered. The lack of a more severe phenotype suggests that a functional TCA cycle is not essential for T. gondii replication and for maintenance of the mitochondrial membrane potential.

Design of a Risk based Control System for Toxoplasma gondii in a pork supply chain

NARCIS (Netherlands)

Heres, L.; Swanenburg, M.; Koeijer, de A.A.; Boender, G.J.; Oorburg, D.; Urlings, B.; Wisselink, H.J.

2015-01-01

Toxoplasma gondii is recognized as one of the major foodborne pathogens. The European Food Safety Authority (EFSA) concluded that T. gondii is one of the public health hazards in pigs to be covered within a modern meat inspection and advised to include serological testing of pigs and audits of pig

Behavioral changes in Rattus norvegicus coinfected by Toxocara canis and Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Maisa Leite de Queiroz

2013-02-01

Full Text Available Using an elevated plus maze apparatus and an activity cage, behavioral changes in Rattus norvegicus concomitantly infected by Toxocara canis and Toxoplasma gondii were studied, during a period of 120 days. Rats infected by Toxocara canis or Toxoplasma gondii showed significant behavioral changes; however, in the group coinfected by both parasites a behavioral pattern similar to that found in the group not infected was observed thirty days after infection, suggesting the occurrence of modulation in the behavioral response.

High seroprevalence of Toxoplasma gondii infection in a subset of Mexican patients with work accidents and low socioeconomic status.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Torres-Castorena, Alejandro; Liesenfeld, Oliver; Estrada-Martínez, Sergio; Urbina-Álvarez, Jesús D

2012-01-11

Toxoplasma gondii has been associated with reflex impairment and traffic accidents. It is unknown whether Toxoplasma infection might be associated with work accidents. Therefore, using a case-control seroprevalence study design, 133 patients with a recent work accident and 266 control subjects of the general population from the same region were examined with enzyme-linked immunoassays for the presence and levels of anti-Toxoplasma IgG antibodies and anti-Toxoplasma IgM antibodies. Socio-demographic, work, clinical and behavioral characteristics from each worker were obtained. Eleven (8.3%) of 133 patients, and 14 (5.3%) of 266 controls had anti-T. gondii IgG antibodies. Anti-T. gondii IgG levels were higher than 150 IU/ml in 8 (6%) patients and 10 (3.8%) controls. Anti-T. gondii IgM antibodies were found in one (0.8%) of the workers, and in 6 (2.3%) of the controls. No statistically significant differences in the IgG seroprevalences, frequencies of high IgG levels, and IgM seroprevalences among patients and controls were found. In contrast, a low socio-economic level in patients with work accidents was associated with Toxoplasma seropositivity (P = 0.01). Patients with work accidents and low socioeconomic status showed a significantly (OR = 3.38; 95% CI: 0.84-16.06; P = 0.04) higher seroprevalence of T. gondii infection than controls of the same socioeconomic status (15.1% vs. 5%, respectively). Multivariate analysis showed a positive association of T. gondii infection with boar meat consumption (OR = 3.04; 95% CI: 1.03-8.94; P = 0.04). In contrast, a negative association between T. gondii infection and national trips (OR = 0.40; 95% CI: 0.17-0.96; P = 0.04), sausage consumption (OR = 0.20; 95% CI: 0.05-0.68; P = 0.01), and ham consumption (OR = 0.16; 95% CI: 0.05-0.51; P = 0.002) was found. In the study described here seropositivity to T. gondii was associated to work accidents in a subset of patients with low socioeconomic status. This is the first report of an

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 ...

Risk factors related to Toxoplasma gondii seroprevalence in indoor-housed Dutch dairy goats.

Science.gov (United States)

Deng, Huifang; Dam-Deisz, Cecile; Luttikholt, Saskia; Maas, Miriam; Nielen, Mirjam; Swart, Arno; Vellema, Piet; van der Giessen, Joke; Opsteegh, Marieke

2016-02-01

Toxoplasma gondii can cause disease in goats, but also has impact on human health through food-borne transmission. Our aims were to determine the seroprevalence of T. gondii infection in indoor-housed Dutch dairy goats and to identify the risk factors related to T. gondii seroprevalence. Fifty-two out of ninety approached farmers with indoor-kept goats (58%) participated by answering a standardized questionnaire and contributing 32 goat blood samples each. Serum samples were tested for T. gondii SAG1 antibodies by ELISA and results showed that the frequency distribution of the log10-transformed OD-values fitted well with a binary mixture of a shifted gamma and a shifted reflected gamma distribution. The overall animal seroprevalence was 13.3% (95% CI: 11.7–14.9%), and at least one seropositive animal was found on 61.5% (95% CI: 48.3–74.7%) of the farms. To evaluate potential risk factors on herd level, three modeling strategies (Poisson, negative binomial and zero-inflated) were compared. The negative binomial model fitted the data best with the number of cats (1–4 cats: IR: 2.6, 95% CI: 1.1–6.5; > = 5 cats:IR: 14.2, 95% CI: 3.9–51.1) and mean animal age (IR: 1.5, 95% CI: 1.1–2.1) related to herd positivity. In conclusion, the ELISA test was 100% sensitive and specific based on binary mixture analysis. T. gondii infection is prevalent in indoor housed Dutch dairy goats but at a lower overall animal level seroprevalence than outdoor farmed goats in other European countries, and cat exposure is an important risk factor.

Toxoplasma gondii antibodies in domiciled cats from rio branco Municipality, Acre State, Brazil

Directory of Open Access Journals (Sweden)

Soraia Figueiredo de Souza

2015-12-01

Full Text Available Blood samples were collected from 89 cats to assess the prevalence of IgG antibodies against Toxoplasma gondii by indirect immunofluorescence (IIF and the possible risk factors associated with feline Toxoplasma gondii infection. An epidemiological questionnaire was developed and implemented for owners of domestic cats domiciled in Rio Branco, Acre. The results were statistically evaluated with the odds ratio and chi-square tests, considering the significance level of 5%. Of 89 animals’ samples, 22 had antibodies against Toxoplasma gondii. Among the 22 reactive animals, 15 (68.19% were female, 15 (68.19% were less than one year old and 20 (90% were cross breed. Concerning risk factors, there was no difference (p > 0.05 between the variables evaluated by the chi-square test. Moreover, 16 (72% cats were fed a mixed diet, 20 (90% of the cats had hunting habits, 18 (81% had contact with animals of another species, 11 (50% had access to the street, and 22 (95% lived in homes that had areas of grass or dirt. In conclusion, the prevalence of anti-Toxoplasma gondii in domestic cats was 22.7%, and there were no significant risk factors for feline toxoplasmosis in the municipality of Rio Branco, Acre.

[Awareness and infection of Toxoplasma gondii in married childbearing women in Chengde Region].

Science.gov (United States)

Li, Xue-jing; Xu, Tao; Song, Ren-hao

2014-08-01

To understand Toxoplasma gondii infection and awareness condition of married childbearing women in Chengde Region, so as to provide the evidence for the establishment of control measures. Totally 733 married childbearing women who took physical examination in Chengde Hospital of Traditional Chinese Medicine from July to December in 2013 were investigated by questionnaire to understand the awareness condition on T. gondii infection, then 490 women among them from 3 counties and 2 districts were randomly chosen to detect the Toxoplasma antibodies by ELISA. A total of 733 questionnaires were returned, and 126 women knew related knowledge about T. gondii infection, and the awareness rate was 17.19%( 126/733). Sixty-three women were determined as infected cases, and the infection rate was 12.86%( 63/490). The infection rates of the women who with higher educational level, working as medical staff and living in urban were lower, and the awareness rates of them were higher. The infection rate of T. gondii among the married childbearing women in Chengde Region is high, and the awareness rate of them is low. In order to decrease the infection rate as well as to increase the awareness rate of the population, the health education should be strengthened.

Brain cystogenesis capacity of Toxoplasma gondii, avirulent Tehran strain in mice

Directory of Open Access Journals (Sweden)

Mehrzad Saraei

2014-09-01

Full Text Available Objective: To investigate the brain cystogenesis capacity of Tehran strain of Toxoplasma gondii (T. gondii that had been isolated from a patient with lymphadenitis in 1973. Methods: A volume of 0.5 mL mice brain suspension containing 20 tissue cysts of Tehran strain of T. gondii was inoculated intraperitoneally to each of 25 male BALB/c mice. The number of brain cysts was counted in unstained squash-smears for 10 mice during weeks 7-9 and for 15 mice during weeks 13-14 post-infection. Nonparametric test of Mann-Whitney was used to demonstrate means differences. Results: There was a significant difference in the means for the number of brain cysts between weeks 7-9 (228.3依144.8 and weeks 13-14 (1 239.8依429.3 post-infection (P<0.05. The minimum and the maximum of cysts were 70 and 1 531 during weeks 7-9 post-infection, and 12 and 5 170 during weeks 13-14 post-infection, respectively. The mean number of brain cysts in the right cerebral hemisphere was insignificantly higher than that of the left cerebral hemisphere. Furthermore, the number of cysts counted in the right or the left hemispheres was significantly higher than those enumerated for cerebellum+brain stem altogether. Conclusions: It is concluded that the brain cystogenesis capacity of T. gondii, Tehran strain shows enormous variation in mice regarding the duration of infection. In addition, the cystogenesis observed in cerebellum+brain stem is lower than the right and left cerebral hemispheres.

Serosurvey of Leptospira spp. and Toxoplasma gondii in rats captured from two zoos in Southern Brazil.

Science.gov (United States)

Pellizzaro, Maysa; Conrado, Francisco de Oliveira; Martins, Camila Marinelli; Joaquim, Sâmea Fernandes; Ferreira, Fernando; Langoni, Helio; Biondo, Alexander Welker

2017-01-01

Norway rats (Rattus norvegicus) are zoonotic reservoirs for Leptospira spp. and Toxoplasma gondii, and influence diseases in urban areas. Free-ranging and laboratory-raised rats from two zoos in southern Brazil were tested for Leptospira spp. and T. gondii using microscopic agglutination and modified agglutination tests, respectively. Overall, 25.6% and 4.6% free-ranging rats tested positive for Leptospira spp. and T. gondii, respectively, with co-seropositivity occurring in two animals. For laboratory-raised rats, 20% tested positive for Leptospira spp. Also, Leptospira biflexa serovar Patoc and Leptospira noguchii serovar Panama were found. Serosurveys can show the environmental prevalence of zoonotic pathogens.

Anti-N-methyl-D-aspartate receptor encephalitis associated with acute Toxoplasma gondii infection: A case report.

Science.gov (United States)

Cai, Xiaotang; Zhou, Hui; Xie, Yongmei; Yu, Dan; Wang, Zhiling; Ren, Haitao

2018-02-01

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis has been recognized as the most frequent autoimmune encephalitis in children. Several infectious agents have been implicated in anti-NMDA encephalitis. A previously healthy immunocompetent 9-year-old girl first presented with seizures, headaches and vomiting. Cerebrospinal fluid and brain magnetic resonance imaging were normal. After one week onset, the patient gradually developed unexplained personality and behavior changes, accompanied by fever and seizures again. Repeated CSF analysis revealed a slightly lymphocytic predominant pleocytosis and positive anti-NMDAR antibody. A variety of pathogenic examinations were negative, except for positive toxoplasma IgM and IgG. The patient was diagnoses for anti-NMDA encephalitis associated with acute acquired toxoplasma gondii infection. The patient received 10 days azithromycin for treatment of acquired toxoplasma infection. The parents refuse immunotherapy because substantial recovery from clinical symptoms. The patient was substantially recovered with residual mild agitation after therapy for acquired toxoplasma gondii infection. Two months later, the patient was completely devoid of symptoms, and the levels of serum IgM and IgG of toxoplasma gondii were decreased. Acquired toxoplasma gondii infection may trigger anti-NMDAR encephalitis in children, which has not been reported previously. Clinicians should assess the possibility of toxoplasma gondii infection when evaluating a patient with anti-NMDA encephalitis.

Loop-mediated isothermal amplification (LAMP): Early detection of Toxoplasma gondii infection in mice

OpenAIRE

Kong, Qing-Ming; Lu, Shao-Hong; Tong, Qun-Bo; Lou, Di; Chen, Rui; Zheng, Bin; Kumagai, Takashi; Wen, Li-Yong; Ohta, Nobuo; Zhou, Xiao-Nong

2012-01-01

Abstract Background Toxoplasmosis is a widespread zoonotic parasitic disease that occurs in both animals and humans. Traditional molecular assays are often difficult to perform, especially for the early diagnosis of Toxoplasma gondii infections. Here, we established a novel loop-mediated isothermal amplification targeting the 529 bp repeat element (529 bp-LAMP) to detect T. gondii DNA in blood samples of experimental mice infected with tachyzoites of the RH strain. Findings The assay was perf...

Seropositivity of Toxoplasma gondii and Toxocara spp. in Children with Cryptogenic Epilepsy, Benha, Egypt.

Science.gov (United States)

Eraky, Maysa Ahmad; Abdel-Hady, Soha; Abdallah, Karim Fetouh

2016-06-01

The present study aimed to investigate the possible association of Toxoplasma gondii and Toxocara spp. infections with cryptogenic epilepsy in children. The study was carried out between June 2014 and March 2015. Total 90 children (40 with cryptogenic epilepsy, 30 with non-cryptogenic epilepsy, and 20 healthy control children) were evaluated to determine the anti-Toxocara and anti-T. gondii IgG seropositivity using ELISA kits. Epileptic cases were selected from those attending the pediatrics outpatient clinic of Benha University Hospital, Pediatrics Neurology Unit, and from Benha Specialized Hospital of children. The results showed that the level of anti-T. gondii IgG seropositivity was significantly higher among children with cryptogenic epilepsy (20%) than among children with non-cryptogenic children (0%). In healthy controls (10%), there was no association between toxocariasis seropositivity and cryptogenic epilepsy (only 5.7%; 4 out of 70 cases) among cases and 10% (2 out of 20) among controls. Among toxocariasis IgG positive cases, 3 (7.5%) were cryptogenic, and only 1 (3.3%) was non-cryptogenic. These statistically significant results support the association between T. gondii infection and cryptogenic epilepsy while deny this association with toxocariasis.

Prevalence of Toxoplasma gondii infections in Pennsylvania black bears, Ursus americanus.

Science.gov (United States)

Briscoe, N; Humphreys, J G; Dubey, J P

1993-10-01

Serum samples from 665 hunter-killed black bears killed in 1989 to 1992 throughout Pennsylvania (USA) were tested for Toxoplasma gondii antibodies by the agglutination test in dilutions of 1:25, 1:50, and 1:500. Toxoplasma gondii antibodies were found in 535 of 665 (80%) bears. Considering the highest dilutions at which antibodies were detected, prevalences were 10% at 1:25, 37% at 1:50 and 33% at 1:500. No significant difference in antibody prevalence was found between males (79%) and females (80%), but a significant difference was found between juvenile (65%) and adult (83%) bears.

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.

Enrofloxacin is able to control Toxoplasma gondii infection in both in vitro and in vivo experimental models.

Science.gov (United States)

Barbosa, Bellisa Freitas; Gomes, Angelica Oliveira; Ferro, Eloisa Amália Vieira; Napolitano, Danielle Reis; Mineo, José Roberto; Silva, Neide Maria

2012-06-08

Currently, toxoplasmosis is treated with sulfadiazine and pyrimethamine. However, this treatment presents several adverse side effects; thus, there is a critical need for the development and evaluation of new drugs, which do not present the same problems of the standard therapy. Enrofloxacin is a fluoroquinolone antibiotic known to control infection against several bacteria in veterinary medicine. Recently, this drug has demonstrated protective effects against protozoan parasites such as Neospora caninum. The present study aimed to determine the effect of enrofloxacin in the control of Toxoplasma gondii infection. For this purpose, human foreskin fibroblast (HFF) cells were infected with T. gondii RH strain and treated with sulfadiazine, penicillin/streptomycin, pyrimethamine, or enrofloxacin. Following treatment, we analyzed the infection index, parasite intracellular proliferation and the number of plaques. Additionally, tissue parasitism and histological changes were investigated in the brain of Calomys callosus that were infected with T. gondii (ME49 strain) and treated with either sulfadiazine or enrofloxacin. Enrofloxacin was able to reduce the infection index, intracellular proliferation and the number of plaques in HFF cells infected by T. gondii in comparison with untreated or penicillin/streptomycin-treated ones. Enrofloxacin was more protective against T. gondii in HFF infected cells than sulfadiazine treatment (Penrofloxacin or the associations of sulfadiazine plus pyrimethamine, enrofloxacin plus sulfadiazine or enrofloxacin plus pyrimethamine-treatments were able to reduce the plaque numbers in HFF cells infected by T. gondii when compared to medium, penicillin/streptomycin or sulfadiazine alone. In vivo experiments demonstrated that enrofloxacin diminished significantly the tissue parasitism as well as the inflammatory alterations in the brain of C. callosus infected with T. gondii when compared with untreated animals. Based on our findings, it can

The neurotropic parasite Toxoplasma gondii increases dopamine metabolism

Science.gov (United States)

The common parasite Toxoplasma gondii induces behavioral alterations in its hosts including phenotypes increasing the likelihood of its transmission in rodents and reports of psychobehavioral alterations in humans. We have found that elevated levels of dopamine are associated with the encysted stage...

Age-related Toxoplasma gondii seroprevalence in Dutch wild boar inconsistent with lifelong persistence of antibodies.

Directory of Open Access Journals (Sweden)

Marieke Opsteegh

Full Text Available Toxoplasma gondii is an important zoonotic pathogen that is best known as a cause of abortion or abnormalities in the newborn after primary infection during pregnancy. Our aim was to determine the prevalence of T. gondii in wild boar to investigate the possible role of their meat in human infection and to get an indication of the environmental contamination with T. gondii. The presence of anti-T. gondii antibodies was determined by in-house ELISA in 509 wild boar shot in 2002/2003 and 464 wild boar shot in 2007. Most of the boar originated from the "Roerstreek" (n = 673 or the "Veluwe" (n = 241. A binormal mixture model was fitted to the log-transformed optical density values for wild boar up to 20 months old to estimate the optimal cut-off value (-0.685 and accompanying sensitivity (90.6% and specificity (93.6%. The overall seroprevalence was estimated at 24.4% (95% CI: 21.1-27.7%. The prevalence did not show variation between sampling years or regions, indicating a stable and homogeneous infection pressure from the environment. The relation between age and seroprevalence was studied in two stages. Firstly, seroprevalence by age group was determined by fitting the binary mixture model to 200 animals per age category. The prevalence showed a steep increase until approximately 10 months of age but stabilized at approximately 35% thereafter. Secondly, we fitted the age-dependent seroprevalence data to several SIR-type models, with seropositives as infected (I and seronegatives as either susceptible (S or resistant (R. A model with a recovery rate (SIS was superior to a model without a recovery rate (SI. This finding is not consistent with the traditional view of lifelong persistence of T. gondii infections. The high seroprevalence suggests that eating undercooked wild boar meat may pose a risk of infection with T. gondii.

Seroprevalence of toxoplasma gondii infection among patients admitted to al-zahra hospital, isfahan, iran

International Nuclear Information System (INIS)

Mohaghegh, M.A.; Yazdani, H.; Hadipour, M.; Namdar, F.

2015-01-01

Toxoplasma gondii (T. gondii) infection is one of the most common parasitic infections among humans and other warm-blooded animals worldwide. The aim of this study was to evaluate toxoplasmosis status in patients admitted to Al-Zahra hospital, Isfahan, Iran. Methods: This cross-sectional study was conducted from October 2012 to January 2015. During this period, 716 patients referred to Al-Zahra hospital in Isfahan city, Iran, were studied to investigate the IgG and IgM antibodies against T. gondii using ELISA kit. The data were analysed by Chi-square and Fishers exact tests. In addition, the relation of data with age and sex were also examined. Results: Among 716 patients, 21 patients (2.9%) had positive IgM and 288 patients (40.2%) had positive IgG titer against T. gondii. Data analysis by Chi-square and Fishers exact tests revealed that there was no significant relationship between IgG titer and age (p>0.05). Additionally, there was no relationship between IgM titer and age (p>0.05). The data showed that there was no relationship between IgG and IgM antibody titer and sex (p>0.05). Conclusion: The prevalence of toxoplasmosis in Isfahan inhabitants seems fairly high but it can be concluded that the rate of seropositive patient is moderate comparing to other regions of country. Accordingly, the authors propose that all sensitive patients have to be tested for T. gondii antibody in order to prevent the consequences of disease. (author)

Occurrence of antibodies to Toxoplasma gondii in rheas (Rhea americana and ostriches (Struthio camelus from farms of different Brazilian regions

Directory of Open Access Journals (Sweden)

Amanda Brentano Almeida

Full Text Available This study aimed to verify the occurrence of antibodies againstToxoplasma gondii in rheas (Rhea americana and ostriches (Struthio camelus commercially breeding in Brazil. Blood samples from 20 rheas and 46 ostriches (young and adults were serologically tested using a technique known as modified agglutination test (MAT at an initial titration of 1:16 for ostriches and 1:25 for rheas. Antibodies against T. gondii were found in 50% (10/20 of the rheas, with titers ranging from 1:25 to 1:6,400. The incidence of antibodies against T. gondii in ostriches was 17.4% (8/46 with titers ranging from 1:16 to 1:256. Birds showing titers higher than 1:200 forT. gondii were mainly the young ones. Therefore, rheas and ostriches may be parasitized by T. gondii, showing high levels of antibodies against this parasite.

Toxoplasma gondii acetyl-CoA synthetase is involved in fatty acid elongation (of long fatty acid chains) during tachyzoite life stages.

Science.gov (United States)

Dubois, David; Fernandes, Stella; Amiar, Souad; Dass, Sheena; Katris, Nicholas J; Botté, Cyrille Y; Yamaryo-Botté, Yoshiki

2018-06-01

Apicomplexan parasites are pathogens responsible for major human diseases such as toxoplasmosis caused by Toxoplasma gondii and malaria caused by Plasmodium spp. Throughout their intracellular division cycle, the parasites require vast and specific amounts of lipids to divide and survive. This demand for lipids relies on a fine balance between de novo synthesized lipids and scavenged lipids from the host. Acetyl-CoA is a major and central precursor for many metabolic pathways, especially for lipid biosynthesis. T. gondii possesses a single cytosolic acetyl-CoA synthetase ( Tg ACS). Its role in the parasite lipid synthesis is unclear. Here, we generated an inducible Tg ACS KO parasite line and confirmed the cytosolic localization of the protein. We conducted 13 C-stable isotope labeling combined with mass spectrometry-based lipidomic analyses to unravel its putative role in the parasite lipid synthesis pathway. We show that its disruption has a minor effect on the global FA composition due to the metabolic changes induced to compensate for its loss. However, we could demonstrate that Tg ACS is involved in providing acetyl-CoA for the essential fatty elongation pathway to generate FAs used for membrane biogenesis. This work provides novel metabolic insight to decipher the complex lipid synthesis in T. gondii . Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.

Seroprevalence of Toxoplasma gondii in free-living European mouflon (Ovis orientalis musimon hunted in central Germany

Directory of Open Access Journals (Sweden)

Heddergott Mike

2018-01-01

Full Text Available Despite increasing consumption of mouflon (Ovis orientalis musimon meat in Germany, there is currently no surveillance of Toxoplasma gondii infection in populations of these animals and generally little knowledge about the prevalence of this protozoan in German wild ungulates. Between 2011 and 2015, we collected 138 blood samples from a free-living mouflon population in central German and tested sera for the presence of T. gondii antibodies using a modified agglutination test (MAT, cut-off 1:20. Antibodies were detected in 31 of the 138 samples (22.46%. There was a significant difference in seroprevalence between the different age classes, with antibodies to T. gondii more frequent in adults. In contrast, there was no significant difference in seroprevalence depending on sex and year of sample collection. Game meat is frequently consumed as raw or undercooked meat and may therefore represent a potential source of human infection with T. gondii.

Prevalence of Toxoplasma gondii in native donkeys in Mosul

Directory of Open Access Journals (Sweden)

Kh. J. Hussain

2011-01-01

Full Text Available The aim of the study was to determine the prevalence of Toxoplasma gondii in native donkeys in Mousl, Iraq. Fifty two sera (9 males and 43 females were examined by Latex agglutination test, Modified latex agglutination test with 2- mercaptoethanol test and Indirect ELISA test (Indirect IgG ELISA. The prevalence of Toxoplasma gondii in native donkeys was 46.15 %. Acute cases 8.33% and chronic cases 91.67 % when differentiated by Modified latex agglutination test with 2- mercaptoethanol test. The percentages of female and male infections were 51.16% (22/43 and 22.22% (2/9, respectively by using latex agglutination test, and the titeration of antibodies ranged between 1:20 - 1:1280 and for Indirect IgG ELISA it was 22.72% positive cases.

UNC93B1 mediates host resistance to infection with Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Mariane B Melo

2010-08-01

Full Text Available UNC93B1 associates with Toll-Like Receptor (TLR 3, TLR7 and TLR9, mediating their translocation from the endoplasmic reticulum to the endolysosome, hence allowing proper activation by nucleic acid ligands. We found that the triple deficient '3d' mice, which lack functional UNC93B1, are hyper-susceptible to infection with Toxoplasma gondii. We established that while mounting a normal systemic pro-inflammatory response, i.e. producing abundant MCP-1, IL-6, TNFα and IFNγ, the 3d mice were unable to control parasite replication. Nevertheless, infection of reciprocal bone marrow chimeras between wild-type and 3d mice with T. gondii demonstrated a primary role of hemopoietic cell lineages in the enhanced susceptibility of UNC93B1 mutant mice. The protective role mediated by UNC93B1 to T. gondii infection was associated with impaired IL-12 responses and delayed IFNγ by spleen cells. Notably, in macrophages infected with T. gondii, UNC93B1 accumulates on the parasitophorous vacuole. Furthermore, upon in vitro infection the rate of tachyzoite replication was enhanced in non-activated macrophages carrying mutant UNC93B1 as compared to wild type gene. Strikingly, the role of UNC93B1 on intracellular parasite growth appears to be independent of TLR function. Altogether, our results reveal a critical role for UNC93B1 on induction of IL-12/IFNγ production as well as autonomous control of Toxoplasma replication by macrophages.

Diagnosis of pulmonary infection with Toxoplasma gondii in immunocompromised HIV-positive patients by real-time PCR

DEFF Research Database (Denmark)

Petersen, E; Edvinsson, B; Lundgren, B

2006-01-01

The aim of the study presented here was to evaluate the use of PCR for improving the diagnosis of Toxoplasma gondii infection in immunocompromised hosts. Three hundred thirty-two bronchoalveolar lavage (BAL) fluid samples were analyzed by real-time PCR targeting a 529 bp element of T. gondii. In ...

Seroprevalence of Toxoplasma gondii infection among pregnant women in Cameroon

Directory of Open Access Journals (Sweden)

Anna L. Njunda

2011-09-01

Full Text Available Toxoplasmosis is caused by an intracellular protozoan, Toxoplasma gondii, which has a wide geographical distribution. The congenital form results in a gestational form that can present a temporary parasiteamia that will infect the fetus. For this reason early diagnosis in pregnancy is highly desirable, allowing prompt intervention in cases of infection. The aim of this study was to determine the seroprevalence of Toxoplasma gondii antibodies among pregnant women attending the Douala General Hospital. The study was carried out between March and July 2009, whereby 110 pregnant women were tested for IgG and IgM antibodies and information about eating habits and hygienic conditions was collected using a questionnaire. These women’s ages ranged from 20-44 years old with an average of 29.9 years; the overall IgG and IgM seroprevalence was 70% and 2.73 % respectively. Seroprevalence was significantly high amongst women who ate raw vegetables (76.39%, P<0.05 and there was a significant trend towards a higher seroprevalence in women who did not have a good source of water (75.58%, P<0.05. This research showed that consumption raw vegetables and poor quality drinking water are two risk factors associated with Toxoplasma gondii infection amongst pregnant women attending the Douala General Hospital in Cameroon.

Long-term humoral antibody responses by various serologic tests in pigs orally inoculated with oocysts of four strains of Toxoplasma gondii

DEFF Research Database (Denmark)

Dubey, J.P.; Andrews, C.D.; Thulliez, P.

1997-01-01

Antibody titers to Toxoplasma gondii were determined in 16 pigs orally inoculated with 1000 or 10000 oocysts of one of the four strains (GT-1, ME-49, TS-2, TC-2) of T. gondii. Pigs were euthanized on postinoculation days 103-875 and their tissues were bioassayed for T. gondii. Antibody titers wer...

Sero-prevalence of Toxoplasma gondii in Danish pigs

DEFF Research Database (Denmark)

Kofoed, Kristina Grønbech; Vorslund-Kiær, Mia; Nielsen, Henrik Vedel

2017-01-01

In 2015, the World Health Organisation rated toxoplasmosis as one of the most important food borne zoonotic diseases in the world. In addition, recent studies have associated Toxoplasma gondii sero-positivity with severe mental illnesses such as schizophrenia. Intake of raw or insufficiently cooked...

Metabolic Cooperation of Glucose and Glutamine Is Essential for the Lytic Cycle of Obligate Intracellular Parasite Toxoplasma gondii*

Science.gov (United States)

Nitzsche, Richard; Zagoriy, Vyacheslav; Lucius, Richard; Gupta, Nishith

2016-01-01

Toxoplasma gondii is a widespread protozoan parasite infecting nearly all warm-blooded organisms. Asexual reproduction of the parasite within its host cells is achieved by consecutive lytic cycles, which necessitates biogenesis of significant energy and biomass. Here we show that glucose and glutamine are the two major physiologically important nutrients used for the synthesis of macromolecules (ATP, nucleic acid, proteins, and lipids) in T. gondii, and either of them is sufficient to ensure the parasite survival. The parasite can counteract genetic ablation of its glucose transporter by increasing the flux of glutamine-derived carbon through the tricarboxylic acid cycle and by concurrently activating gluconeogenesis, which guarantee a continued biogenesis of ATP and biomass for host-cell invasion and parasite replication, respectively. In accord, a pharmacological inhibition of glutaminolysis or oxidative phosphorylation arrests the lytic cycle of the glycolysis-deficient mutant, which is primarily a consequence of impaired invasion due to depletion of ATP. Unexpectedly, however, intracellular parasites continue to proliferate, albeit slower, notwithstanding a simultaneous deprivation of glucose and glutamine. A growth defect in the glycolysis-impaired mutant is caused by a compromised synthesis of lipids, which cannot be counterbalanced by glutamine but can be restored by acetate. Consistently, supplementation of parasite cultures with exogenous acetate can amend the lytic cycle of the glucose transport mutant. Such plasticity in the parasite's carbon flux enables a growth-and-survival trade-off in assorted nutrient milieus, which may underlie the promiscuous survival of T. gondii tachyzoites in diverse host cells. Our results also indicate a convergence of parasite metabolism with cancer cells. PMID:26518878

Loop-mediated isothermal amplification (LAMP): early detection of Toxoplasma gondii infection in mice.

Science.gov (United States)

Kong, Qing-Ming; Lu, Shao-Hong; Tong, Qun-Bo; Lou, Di; Chen, Rui; Zheng, Bin; Kumagai, Takashi; Wen, Li-Yong; Ohta, Nobuo; Zhou, Xiao-Nong

2012-01-03

Toxoplasmosis is a widespread zoonotic parasitic disease that occurs in both animals and humans. Traditional molecular assays are often difficult to perform, especially for the early diagnosis of Toxoplasma gondii infections. Here, we established a novel loop-mediated isothermal amplification targeting the 529 bp repeat element (529 bp-LAMP) to detect T. gondii DNA in blood samples of experimental mice infected with tachyzoites of the RH strain. The assay was performed with Bst DNA polymerase at 65°C for 1 h. The detection limit of the 529 bp-LAMP assay was as low as 0.6 fg of T. gondii DNA. The sensitivity of this assay was 100 and 1000 fold higher than that of the LAMP targeting B1 gene (B1-LAMP) and nested PCR targeting 529 bp repeat element (529 bp-nested PCR), respectively. The specificity of the 529 bp-LAMP assay was determined using the DNA samples of Trypanosoma evansi, Plasmodium falciparum, Paragonimus westermani, Schistosoma japonicum, Fasciola hepatica and Angiostrongylus cantonensis. No cross-reactivity with the DNA of any parasites was found. The assay was able to detect T. gondii DNA in all mouse blood samples at one day post infection (dpi). We report the following findings: (i) The detection limit of the 529 bp-LAMP assay is 0.6 fg of T. gondii DNA; (ii) The assay does not involve any cross-reactivity with the DNA of other parasites; (iii) This is the first report on the application of the LAMP assay for early diagnosis of toxoplasmosis in blood samples from experimentally infected mice. Due to its simplicity, sensitivity and cost-effectiveness for common use, we suggest that this assay should be used as an early diagnostic tool for health control of toxoplasmosis.

Carne de consumo e risco de transmissão de Toxoplasma gondii

OpenAIRE

Rosado, Joana de Carvalho Serra

2009-01-01

O consumo de carne de suíno (Sus domesticus) é considerado o maior factor de risco para a transmissão da toxoplasmose aos humanos. No entanto, apesar dos suínos serem muito usados na gastronomia portuguesa, tanto pelo consumo de carne, como pelo de enchidos, pouco se sabe sobre a prevalência e caracterização genética de Toxoplasma gondii nestes produtos alimentares, no país. Neste trabalho, pretendeu-se determinar a seroprevalência de anticorpos IgG anti-T. gondii em suínos de ...

Seroepidemiology of Toxoplasma gondii infection in drivers involved in road traffic accidents in the metropolitan area of Guadalajara, Jalisco, Mexico.

Science.gov (United States)

Galván-Ramírez, Ma de la Luz; Sánchez-Orozco, Laura Verónica; Rodríguez, Laura Rocío; Rodríguez, Saúl; Roig-Melo, Enrique; Troyo Sanromán, Rogelio; Chiquete, Erwin; Armendáriz-Borunda, Juan

2013-10-11

The prevalence of toxoplasmosis in the general population of Guadalajara, Mexico, is around 32%. Toxoplasmosis can cause ocular lesions and slowing of reaction reflexes. Latent toxoplasmosis has been related with traffic accidents. We aimed to assess the prevalence of anti-Toxoplasma gondii antibodies and visual impairments related with traffic accidents in drivers from the metropolitan Guadalajara. We prospectively evaluated the prevalence of IgG and IgM anti-T. gondii antibodies in 159 individuals involved in traffic accidents, and in 164 control drivers never involved in accidents. Cases of toxoplasmosis reactivation or acute infection were detected by PCR in a subset of 71 drivers studied for the presence of T. gondii DNA in blood samples. Ophthalmologic examinations were performed in drivers with IgG anti-T. gondii antibodies in search of ocular toxoplasmosis. Fifty-four (34%) traffic accident drivers and 59 (36%) controls were positive to IgG anti-T. gondii antibodies (p = 0.70). Among the 113 seropositive participants, mean anti-T. gondii IgG antibodies titers were higher in traffic accident drivers than in controls (237.9 ± 308.5 IU/ml vs. 122.9 ± 112.7 IU/ml, respectively; p = 0.01 by Student's t test, p = 0.037 by Mann-Whitney U test). In multivariate analyses, anti-T. gondii IgG antibody titers were consistently associated with an increased risk of traffic accidents, whereas age showed an inverse association. The presence of IgM-anti-T. gondii antibodies was found in three (1.9%) subjects among traffic accident drives, and in two (1.2%) controls. Three (4.2%) samples were positive for the presence of T. gondii DNA, all among seropositive individuals. No signs of ocular toxoplasmosis were found in the entire cohort. Moreover, no other ocular conditions were found to be associated with the risk of traffic accidents in a multivariate analysis. Anti-T. gondii antibody titers are associated with the risk of traffic accidents. We could not determine any

Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by {sup 60}Co; Avaliacao da imunidade e protecao induzida em modelos experimentais por extrato soluvel de taquizoitos de Toxoplasma gondii irradiado por {sup 60}Co

Energy Technology Data Exchange (ETDEWEB)

Costa, Andrea da

2013-07-01

Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

New Toxoplasma gondii genotypes isolated from free-range chickens from the Fernando de Noronha, Brazil: unexpected findings

Science.gov (United States)

Worldwide comparison of Toxoplasma gondii isolates from free range chickens has indicated that T. gondii isolates from Brazil are phenotypically and genetically different than isolates from other countries; most strains from Brazil are pathogenic to mice, there is great genetic variability, most iso...

Immunity Status of Blood Donors Regarding Toxoplasma gondii Infection in a Low-Income District of Abidjan, Côte d’Ivoire, West Africa

Directory of Open Access Journals (Sweden)

Liliane Siransy

2016-01-01

Full Text Available Background. Toxoplasmosis is a widespread cosmopolitan anthropozoonosis, which affects more than a third of the world population. Except the modes of transmission well known, Toxoplasma gondii can be transmitted during transplantation or blood transfusion. The aim of this study is to determine the prevalence of IgG and IgM Toxoplasma gondii and to estimate the potential risk by blood products. Methods. This is a cross-sectional study on the research for Toxoplasma gondii antibodies (IgG and IgM blood donors performed by ELISA. Results. An overall seroprevalence of Toxoplasma gondii among blood donors recruited was 67.92% (n=72. Among these, 68 have Toxoplasma gondii IgG (64.15%, 12 Toxoplasma gondii IgM (11.32%, and 4 (3.77% both. The risk varies between 8 for 100000 and 172 for 100000 donations. Conclusion. The need to strengthen security measures for people multitransfused, immunocompromised, and pregnant women to reduce the transmission of toxoplasmosis is important.

Goats reinfected with Toxoplasma gondii: loss of viable prolificacy and gross revenue

Directory of Open Access Journals (Sweden)

H. M. Silva

2015-10-01

Full Text Available ABSTRACTWe determined the reproductive parameters and clinical disorders in pregnant goats infected and reinfected with Toxoplasma gondii, and posteriorly the loss of gross revenue due to congenital toxoplasmosis was estimated. Of the 25 non-pregnant females negative for T. gondii, 20 were orally inoculated (ME 49 strain and of these, 15 pregnant females chronically infected were orally reinoculated (VEG strain with T. gondii oocysts. Five groups were formed (n=5: GI, GII and GIII (reinoculations at 40, 80 and 120 days of gestation, respectively, GIV (inoculation and GV (no inoculation. Clinical and serological exams were performed on days 0 (prior to inoculation, 3, 6 9, 15 and 21 and every 7 days post-inoculation. Exams were also performed on day 3 and every 7 days post-reinoculation. Reproductive management was performed on all females and initiated when the females infected displayed IgG titers IFAT<1,024. From the average prolificacy indexes of each experimental group were estimated: total production of kilograms of live weight (total kg LW of goats for slaughter, gross revenue and loss of gross revenue in U.S. dollars (US$, designed for a herd of 1,000 matrices. The unviable prolificacy indexes were 0.8 (GI, 1.2 (GII and 0.2 (GIII. Clinical disorders affected 57.1% (GI, 75.0% (GII and 16.7% (GIII of the offspring of goats reinfected with T. gondii. Congenital toxoplasmosis in goats reinfected resulted in the loss of 26.5% of gross revenues, being GI (US$ 10,577.60 or 57.1% and GII (US$ 12,693.12 or 60% holders of the highest values and percentages of economic losses. It was found that congenital toxoplasmosis reinfection cause clinical disorders in goats chronically infected with T. gondii and their offspring with birth of unviable animals and loss of gross revenue, at different stages of pregnancy (40, 80 and 120 days of gestation, being in the initial and intermediate stages of pregnancy the largest estimates of these losses.

Aspectos ultraestruturais do processo de divisão do Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Wanderley de Souza

1974-02-01

Full Text Available Neste trabalho é feita uma revisão sobre alguns aspectos biológicos do Toxoplasma gondii, principalmente sobre a ultraestrutura da forma interfásica e as modificações ultraestruturais que ocorrem no parasito durante o seu processo de divisão. Considera-se inicialmente o processo de divisão binária admitindo-se, porém, a possibilidade de que as imagens interpretadas como senão de divisão binária representem estágios da divisão por endodiogenia. Quanto à endodiogenia descrevem-se as alterações que ocorrem na "parasito mãe" durante o processo de formação dos dois "parasitos filhos". Este processo é semelhante no Toxoplasma gondii, Besnoitia jellisoni, Sarcocystis tenella e Frenkelia. Discute-se a possibilidade da formação de mais de dois "parasitos filhos" por um processo de endopoligenia, bem como o processo de esquizogonia. Os resultados mais recentes mostram que não existe esquizogonia nas formas vsgetativas do Toxoplasma gondii, senão que as imagens interpretadas como tal, ao microscópio ótico, são o resultado de endodiogenias sucessivas em que os endozoitas formados permanecem ligados entre si pela região posterior. A esquizogonia é, no entanto, encontrada nas formas que se desenvolvem no interior de células epiteliais do intestino do gato, que é o hospedeiro definitivo do Toxoplasma gondii. Discute-se o conceito de esquizogonia, comparando-o em três protozoários: Eimeria bovis, E. callospermophili e Plasmodium juxtanucleare, que apresentam diferenças entre si quanto ao processo de iniciação da individualização dos "parasitos filhos". Refere-se à recente hipótese que considera a endodiogenia como o processo fundamental de divisão dos esporozoárlos, ocorrendo na fase final da esquizogonia. Finalmente é acentuado o papel que a microscopia eletrônica aliada às modernas técnicas de citoquímica e imunocitoquimica poderá desempenhar no sentido de um melhor conhecimento da biologia do Toxoplasma

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.

Seroprevalence of Toxoplasma gondii in mainland and sub-Antarctic New Zealand sea lion (Phocarctos hookeri) populations.

Science.gov (United States)

Michael, S A; Howe, L; Chilvers, B L; Morel, Pch; Roe, W D

2016-09-01

To investigate the seroprevalence of antibodies to Toxoplasma gondii in New Zealand sea lions (Phocarctos hookeri), as a potential contributor to reproductive failure. Archived sera were sourced from New Zealand sea lions from two recolonising mainland populations in the Otago Peninsula (n=15) and Stewart Island (n=12), as well as a declining population at Enderby Island (n=28) in the New Zealand sub-Antarctic. Sera were tested for antibodies to T. gondii using a commercially available ELISA (with samples considered positive if the sample to positive ratio was >30%), and latex agglutination test (LAT; with titres ≥1:32 considered positive). Western blot analysis was used to validate the results of a subset of 14 samples. Five samples from sea lions in mainland locations were confirmed positive for antibodies to T. gondii. Two adult females exhibited high LAT antibody titres (min 1:2048, max 1:4096) on both occasions when sampled 1 and 2 years apart, respectively. No animals from Enderby Island were seropositive. Toxoplasma gondii infection is unlikely to be a major contributor to poor reproductive success in New Zealand sea lions. However, continued surveillance is pertinent to assess subclinical and clinical impacts of the parasite on these threatened populations. The commercial tests evaluated here, with further species-specific threshold refinement could provide a fast, inexpensive and reliable indicator of T. gondii exposure in New Zealand sea lions.

Portugal and Angola: similarities and differences in Toxoplasma gondii seroprevalence and risk factors in pregnant women.

Science.gov (United States)

Lobo, M L; Patrocinio, G; Sevivas, T; DE Sousa, B; Matos, O

2017-01-01

In this study we determined the presence of IgM/IgG antibodies to Toxoplasma gondii in sera of 155 and 300 pregnant women from Lisbon (Portugal) and Luanda (Angola), respectively, and evaluated the potential risk factors associated with this infection. DNA detection was performed by PCR assays targeting T. gondii regions (RE/B1). Overall, 21·9% (10·9% IgG, 10·9% IgG/IgM) of the Lisbon women and 27·3% (23·7%, IgG, 2% IgM, 1·7% IgG/IgM) of the Luanda women had antibodies to T. gondii. Single variable and binary logistic regression analyses were conducted. Based on the latter, contacts with cats (family/friends), and having more than two births were identified as risk factors for Toxoplasma infection in Lisbon women. In Luanda, the risk factors for T. gondii infection suggested by the single variable analysis (outdoor contact with cats and consumption of pasteurized milk/dairy products) were not confirmed by binary logistic regression. This study shows original data from Angola, and updated data from Portugal in the study of infection by T. gondii in pregnant women, indicating that the prevalence of anti-Toxoplasma antibodies is high enough to alert the government health authorities and implement appropriate measures to control this infection.

Seroprevalence and risk factors of Toxoplasma gondii infection ...

African Journals Online (AJOL)

The infection is also associated with human immune deficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). In Rwanda, the burden and risk factors of T. gondii infection among pregnant women and among HIV infected pregnant women is largely unknown. This cross-sectional study aimed at determining the ...

HLA-DQBl*0402 alleles polymorphisms detected in Javanese HIV patients with positive anti-Toxoplasma gondii IgM

Science.gov (United States)

Sari, Yulia; Haryati, Sri; Prasetyo, Afiono Agung; Hartono, Adnan, Zainal Arifin

2017-02-01

The human leukocyte antigen (HLA)-DQB1 gene polymorphisms may associated with the infection risk of Toxoplasma gondii in HIV patients. The HLA-DQB1*0402 in HIV-1-positive patients could be considered risk factors for developing neurological opportunistic infections, mainly Toxoplasma encephalitis. However, the HLA-DQB1*0402 gene polymorphisms status in the Javanese HIV patients is unknown. This study evaluated the prevalence of HLA-DQB*0402 alleles polymorphisms in Javanese HIV patients with positive anti-Toxoplasma gondii IgM status. Since 2009 our research group performing a molecular epidemiology of blood borne viruses in Central Java Indonesia, by collecting the epidemiological and clinical data from the high risk communities. All blood samples were screened for blood borne pathogens by serological and molecular assays including for HIV and Toxoplasma gondii. The genomic DNA was isolated from the whole blood samples. Genetic polymorphisms of HLA-DQB1*0402 alleles were detected with polymerase chain reaction-sequence-specific primers (PCR-SSPs) technique. The genotypes were defined according to generated fragment patterns in the agarose gel electrophoresis analysis of PCR products. All of the samples were tested at least in duplicate. HLA-DQB1*0402 alleles were detected in 20.8% (16/77) patients and not detected in all HIV positive samples with negative anti-Toxoplasma gondii IgM status (n= 200). The HLA-DQB1*0402 alleles polymorphisms were detected in Javanese HIV patients with positive anti-Toxoplasma gondii IgM. The polymorphisms found may have association with the infection risk of Toxoplasma gondii in HIV patients.

Anti-Toxoplasma gondii secretory IgA in tears of patients with ocular toxoplasmosis: immunodiagnostic validation by ELISA

Directory of Open Access Journals (Sweden)

Maria Isabel Lynch

2009-09-01

Full Text Available Toxoplasma gondii causes posterior uveitis and the specific diagnosis is based on clinical criteria. The presence of anti-T. gondii secretory IgA (sIgA antibodies in patients' tears has been reported and an association was found between ocular toxoplasmosis and the anti-T. gondii sIgA isotype in Brazilian patients. The purpose of this study was to provide an objective validation of the published ELISA test for determining the presence of anti-T. gondii sIgA in the tears of individuals with ocular toxoplasmosis. Tears from 156 patients with active posterior uveitis were analysed; 82 of them presented characteristics of ocular toxoplasmosis (standard lesion and 74 patients presented uveitis due to other aetiologies. Cases of active posterior uveitis were considered standard when a new inflammatory focus satellite to old retinochoroidal scars was observed. The determination of anti-T. gondii sIgA was made using an ELISA test with crude tachyzoite antigenic extracts. Tears were collected without previous stimulation. Detection of sIgA showed 65.9% sensitivity (95% CI = 54.5-74.4, 71.6% specificity (95% CI = 59.8-81.2, a positive predictive value of 72% (95% CI = 60.3-81.5 and a negative predictive value of 65.4% (95% CI = 54.0-75.4. sIgA reactivity was higher in the tears of patients with active posterior uveitis due to T. gondii (p < 0.05. The test is useful for differentiating active posterior uveitis due to toxoplasmosis from uveitis caused by other diseases.

Anti-Toxoplasma gondii secretory IgA in tears of patients with ocular toxoplasmosis: immunodiagnostic validation by ELISA.

Science.gov (United States)

Lynch, Maria Isabel; Malagueño, Elizabeth; Lynch, Luiz Felipe; Ferreira, Silvana; Stheling, Raphael; Oréfice, Fernando

2009-09-01

Toxoplasma gondii causes posterior uveitis and the specific diagnosis is based on clinical criteria. The presence of anti-T. gondii secretory IgA (sIgA) antibodies in patients' tears has been reported and an association was found between ocular toxoplasmosis and the anti-T. gondii sIgA isotype in Brazilian patients. The purpose of this study was to provide an objective validation of the published ELISA test for determining the presence of anti-T. gondii sIgA in the tears of individuals with ocular toxoplasmosis. Tears from 156 patients with active posterior uveitis were analysed; 82 of them presented characteristics of ocular toxoplasmosis (standard lesion) and 74 patients presented uveitis due to other aetiologies. Cases of active posterior uveitis were considered standard when a new inflammatory focus satellite to old retinochoroidal scars was observed. The determination of anti-T. gondii sIgA was made using an ELISA test with crude tachyzoite antigenic extracts. Tears were collected without previous stimulation. Detection of sIgA showed 65.9% sensitivity (95% CI = 54.5-74.4), 71.6% specificity (95% CI = 59.8-81.2), a positive predictive value of 72% (95% CI = 60.3-81.5) and a negative predictive value of 65.4% (95% CI = 54.0-75.4). sIgA reactivity was higher in the tears of patients with active posterior uveitis due to T. gondii (p < 0.05). The test is useful for differentiating active posterior uveitis due to toxoplasmosis from uveitis caused by other diseases.

The novel protein BboRhop68 is expressed by intraerytrhocytic stages of Babesia bovis

Science.gov (United States)

The apical complex of intracellular hemoparasites contains organelles like micronemes and rhoptries, specialized structures required for adherence and invasion of host cells. Several molecules discharged from rhoptries have been identified from Plasmodium spp., but only a single rhoptry associated p...

Genetically attenuated P36p-deficient Plasmodium berghei sporozoites confer long-lasting and partial cross-species protection

NARCIS (Netherlands)

Douradinha, Bruno; van Dijk, Melissa R.; Ataide, Ricardo; van Gemert, Geert-Jan; Thompson, Joanne; Franetich, Jean-Francois; Mazier, Dominique; Luty, Adrian J. F.; Sauerwein, Robert; Janse, Chris J.; Waters, Andrew P.; Mota, Maria M.

2007-01-01

Immunisation with live, radiation-attenuated sporozoites (RAS) or genetically attenuated sporozoites (GAS) of rodent plasmodial parasites protects against subsequent challenge infections. We recently showed that immunisation with Plasinodium berghei GAS that lack the microneme protein P36p protects

Serological Survey and Factors Associated with Toxoplasma gondii Infection in Domestic Goats in Myanmar

Science.gov (United States)

Bawm, Saw; Maung, Wint Yi; Win, Myat Yee; Thu, May June; Chel, Hla Myet; Khaing, Tin Aye; Wai, Soe Soe; Htun, Lat Lat; Myaing, Tin Tin; Tiwananthagorn, Saruda; Igarashi, Makoto; Katakura, Ken

2016-01-01

Goat farming is important for the livelihood of millions of rural people because it contributes to food security and creation of assets. However, infection of goats with Toxoplasma gondii could be a source of parasite transmission to humans. The information on T. gondii infection of goat was not reported yet in Myanmar. A total of 119 goat serum samples were collected from three cities in the central region of Myanmar for T. gondii antibody survey. With the occurrence value obtained in this first study, a second one, more complete, with larger number (162) of animals and properties, was carried out and the risk factors and prevalence were determined. In both studies the samples were analyzed by the LAT. Of these, 32 (11.4%) samples were showed to be positive. The infection was associated with the presence of cats at the farm (odds ratio [OR] = 4.66, 95% confidential interval [CI] = 1.03–21.06), farming with different animal species (sheep, cattle, and pigs) (OR = 4.33, 95% CI = 1.57–11.94), and farming without good management practices (OR = 0.23, 95% CI = 0.06–0.83). This is the first T. gondii prevalence study in goats in the country. PMID:26904362

Serological Survey and Factors Associated with Toxoplasma gondii Infection in Domestic Goats in Myanmar

Directory of Open Access Journals (Sweden)

Saw Bawm

2016-01-01

Full Text Available Goat farming is important for the livelihood of millions of rural people because it contributes to food security and creation of assets. However, infection of goats with Toxoplasma gondii could be a source of parasite transmission to humans. The information on T. gondii infection of goat was not reported yet in Myanmar. A total of 119 goat serum samples were collected from three cities in the central region of Myanmar for T. gondii antibody survey. With the occurrence value obtained in this first study, a second one, more complete, with larger number (162 of animals and properties, was carried out and the risk factors and prevalence were determined. In both studies the samples were analyzed by the LAT. Of these, 32 (11.4% samples were showed to be positive. The infection was associated with the presence of cats at the farm (odds ratio [OR] = 4.66, 95% confidential interval [CI] = 1.03–21.06, farming with different animal species (sheep, cattle, and pigs (OR = 4.33, 95% CI = 1.57–11.94, and farming without good management practices (OR = 0.23, 95% CI = 0.06–0.83. This is the first T. gondii prevalence study in goats in the country.

Toxoplasma gondii infection induces dendritic retraction in basolateral amygdala accompanied by reduced corticosterone secretion

Directory of Open Access Journals (Sweden)

Rupshi Mitra

2013-03-01

Pathological anxiety is thought to reflect a maladaptive state characterized by exaggerated fear. Naturally occurring perturbations that reduce fear can be crucial in the search for new treatments. The protozoan parasite Toxoplasma gondii invades rat brain and removes the fear that rats have of cat odors, a change believed to be parasitic manipulation of host behavior aimed at increasing parasite transmission. It is likely that mechanisms employed by T. gondii can be used as a heuristic tool to understand possible means of fear reduction in clinical settings. Male Long-Evans rats were infected with T. gondii and compared with sham-infected animals 8 weeks after infection. The amount of circulating plasma corticosterone and dendritic arborization of basolateral amygdala principal neurons were quantified. Previous studies have shown that corticosterone, acting within the basolateral amygdala, enhances the fear response to environmental stimuli. Here we show that T. gondii infection causes a dendritic retraction in basolateral amygdala neurons. Such dendritic retraction is accompanied by lower amounts of circulating corticosterone, both at baseline and when induced by an aversive cat odor. The concerted effects of parasitism on two pivotal physiological nodes of the fear response provide an animal model relevant to interactions between stress hormones and amygdalar plasticity.

Detection of Toxoplasma gondii DNA in horse meat from supermarkets in France and performance evaluation of two serological tests

OpenAIRE

Aroussi Abdelkrim; Vignoles Philippe; Dalmay François; Wimel Laurence; Dardé Marie-Laure; Mercier Aurélien; Ajzenberg Daniel

2015-01-01

In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii an...

Recombinase polymerase amplification (RPA) combined with lateral flow (LF) strip for detection of Toxoplasma gondii in the environment.

Science.gov (United States)

Wu, Y D; Xu, M J; Wang, Q Q; Zhou, C X; Wang, M; Zhu, X Q; Zhou, D H

2017-08-30

Toxoplasma gondii infects all warm-blooded vertebrates, resulting in a great threat to human health and significant economic loss to the livestock industry. Ingestion of infectious oocysts of T. gondii from the environment is the major source of transmission. Detection of T. gondii oocysts by existing methods is laborious, time-consuming and expensive. The objective of the present study was to develop a recombinase polymerase amplification (RPA) method combined with a lateral flow (LF) strip for detection of T. gondii oocysts in the soil and water. The DNA of T. gondii oocysts was amplified by a pair of specific primers based on the T. gondii B1 gene over 15min at a constant temperature ranging from 30°C to 45°C using RPA. The amplification product was visualized by the lateral flow (LF) strip within 5min using the specific probe added to the RPA reaction system. The sensitivity of the established assay was 10 times higher than that of nested PCR with a lower detection limit of 0.1 oocyst per reaction, and there was no cross-reactivity with other closely related protozoan species. Fifty environmental samples were further assessed for the detection validity of the LF-RPA assay (B1-LF-RPA) and compared with nested PCR based on the B1 gene sequence. The B1-LF-RPA and nested PCR both showed that 5 out of the 50 environmental samples were positive. The B1-LF-RPA method was also proven to be sufficiently tolerant of existing inhibitors in the environment. In addition, the advantages of simple operation, speediness and cost-effectiveness make B1-LF-RPA a promising molecular detection tool for T. gondii. Copyright © 2017 Elsevier B.V. All rights reserved.

Toxoplasma gondii Infection in Mice Impairs Long-Term Fear Memory Consolidation through Dysfunction of the Cortex and Amygdala.

Science.gov (United States)

Ihara, Fumiaki; Nishimura, Maki; Muroi, Yoshikage; Mahmoud, Motamed Elsayed; Yokoyama, Naoaki; Nagamune, Kisaburo; Nishikawa, Yoshifumi

2016-10-01

Chronic infection with Toxoplasma gondii becomes established in tissues of the central nervous system, where parasites may directly or indirectly modulate neuronal function. Epidemiological studies have revealed that chronic infection in humans is a risk factor for developing mental diseases. However, the mechanisms underlying parasite-induced neuronal dysfunction in the brain remain unclear. Here, we examined memory associated with conditioned fear in mice and found that T. gondii infection impairs consolidation of conditioned fear memory. To examine the brain pathology induced by T. gondii infection, we analyzed the parasite load and histopathological changes. T. gondii infects all brain areas, yet the cortex exhibits more severe tissue damage than other regions. We measured neurotransmitter levels in the cortex and amygdala because these regions are involved in fear memory expression. The levels of dopamine metabolites but not those of dopamine were increased in the cortex of infected mice compared with those in the cortex of uninfected mice. In contrast, serotonin levels were decreased in the amygdala and norepinephrine levels were decreased in the cortex and amygdala of infected mice. The levels of cortical dopamine metabolites were associated with the time spent freezing in the fear-conditioning test. These results suggest that T. gondii infection affects fear memory through dysfunction of the cortex and amygdala. Our findings provide insight into the mechanisms underlying the neurological changes seen during T. gondii infection. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Toxoplasma gondii Requires Glycogen Phosphorylase for Balancing Amylopectin Storage and for Efficient Production of Brain Cysts.

Science.gov (United States)

Sugi, Tatsuki; Tu, Vincent; Ma, Yanfen; Tomita, Tadakimi; Weiss, Louis M

2017-08-29

In immunocompromised hosts, latent infection with Toxoplasma gondii can reactivate from tissue cysts, leading to encephalitis. A characteristic of T. gondii bradyzoites in tissue cysts is the presence of amylopectin granules. The regulatory mechanisms and role of amylopectin accumulation in this organism are not fully understood. The T. gondii genome encodes a putative glycogen phosphorylase (TgGP), and mutants were constructed to manipulate the activity of TgGP and to evaluate the function of TgGP in amylopectin storage. Both a stop codon mutant (Pru/TgGP S25stop [expressing a Ser-to-stop codon change at position 25 in TgGP]) and a phosphorylation null mutant (Pru/TgGP S25A [expressing a Ser-to-Ala change at position 25 in TgGp]) mutated at Ser25 displayed amylopectin accumulation, while the phosphorylation-mimetic mutant (Pru/TgGP S25E [expressing a Ser-to-Glu change at position 25 in TgGp]) had minimal amylopectin accumulation under both tachyzoite and bradyzoite growth conditions. The expression of active TgGP S25S or TgGP S25E restored amylopectin catabolism in Pru/TgGP S25A To understand the relation between GP and calcium-dependent protein kinase 2 (CDPK2), which was recently reported to regulate amylopectin consumption, we knocked out CDPK2 in these mutants. Pru Δcdpk2 /TgGP S25E had minimal amylopectin accumulation, whereas the Δcdpk2 phenotype in the other GP mutants and parental lines displayed amylopectin accumulation. Both the inactive S25A and hyperactive S25E mutant produced brain cysts in infected mice, but the numbers of cysts produced were significantly less than the number produced by the S25S wild-type GP parasite. Complementation that restored amylopectin regulation restored brain cyst production to the control levels seen in infected mice. These data suggest that T. gondii requires tight regulation of amylopectin expression for efficient production of cysts and persistent infections and that GP phosphorylation is a regulatory mechanism

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

Science.gov (United States)

Millán, Javier; Cabezón, Oscar; Pabón, Marcela; Dubey, J P; Almería, Sonia

2009-11-12

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 traps during authorized predator control campaigns in Majorca, Balearic Islands, Spain. Antibodies to T. gondii assayed by the modified agglutination test (MAT) were found in 50 (84.7%) of 59 cats with MAT titers of 1:25 in one cat, 1:200 in four cats, 1:500 in seven cats, 1:1000 in nine cats, and >or=1:2000 in 29 cats. Seroprevalence (MAT, 1:25 or more) was significantly higher in adults (94.6%) than in juveniles (cats in Majorca is one of the highest reported worldwide in this species and the highest observed in Europe to date. The results suggest that feral cats in Majorca have a high rate of T. gondii infection with important implications for public health on the island since the seropositive cats are likely to have already shed T. gondii oocysts in the environment.

The effects of quercetin towards reactive oxygen species levels and glutathione in Toxoplasma gondii profilin-exposed adipocytes in vitro

Directory of Open Access Journals (Sweden)

Yulia D.S.

2018-04-01

Full Text Available Toxoplasma gondii (T. gondii has been found to potentially cause adipocyte dysfunction by activating the inflammatory pathways through its profilin. In response to inflammation, adipocytes produce Reactive Oxygen Species (ROS. To scavenge ROS, endogenous or exogenous antioxidants are required. Glutathione (GSH is one of enzimatic antioxidant that abundant in all of body cells. Quercetin, an exogenous antioxidant, can be widely found in natural products. This research aims to explore the effects of quercetin towards ROS and GSH stimulated from T. gondii profilin-exposed adipocytes. To achieve this, adipocytes were exposed to 20 µM T. gondii profilin and treated with four doses of quercetin; 31.25, 62.5, 125, and 250 µM. The results showed that quercetin significantly reduced the ROS levels (p <0,001 and significantly increased GSH (p <0,001 in T. gondii profilin-exposed adipocytes compared to untreated cells, with an effective dose of 62.5µM. This study implies that quercetin might be a promising candidate for development of antioxidant treatment interventions to prevent toxoplasmosis-mediated adipocytopathy.

Is Toxoplasma Gondii Infection Related to Brain and Behavior Impairments in Humans? Evidence from a Population-Representative Birth Cohort.

Directory of Open Access Journals (Sweden)

Karen Sugden

Full Text Available Toxoplasma gondii (T. gondii is a protozoan parasite present in around a third of the human population. Infected individuals are commonly asymptomatic, though recent reports have suggested that infection might influence aspects of the host's behavior. In particular, Toxoplasma infection has been linked to schizophrenia, suicide attempt, differences in aspects of personality and poorer neurocognitive performance. However, these studies are often conducted in clinical samples or convenience samples.In a population-representative birth-cohort of individuals tested for presence of antibodies to T. gondii (N = 837 we investigated the association between infection and four facets of human behavior: neuropsychiatric disorder (schizophrenia and major depression, poor impulse control (suicidal behavior and criminality, personality, and neurocognitive performance. Suicide attempt was marginally more frequent among individuals with T. gondii seropositivity (p = .06. Seropositive individuals also performed worse on one out of 14 measures of neuropsychological function.On the whole, there was little evidence that T. gondii was related to increased risk of psychiatric disorder, poor impulse control, personality aberrations or neurocognitive impairment.

Anti- toxoplasma gondii activity of constituents from Balsamocitrus ...

African Journals Online (AJOL)

Isolation, characterization and anti-Toxoplasma gondii activity of constituents from the CH2Cl2/MeOH (1/1) extract of the roots of the cameroonian plant Balsamocitrus camerunensis L. were investigated in this study. Four known coumarins derivatives were isolated, namely, marmin (1), imperatorin (2), xanthoxyletin (3), ...

Toxoplasma gondii decreases the reproductive fitness in mice

Czech Academy of Sciences Publication Activity Database

Dvořáková-Hortová, K.; Šídlová, A.; Děd, Lukáš; Hladovcová, D.; Vieweg, M.; Weidner, W.; Steger, K.; Stopka, P.; Paradowska-Dogan, A.

2014-01-01

Roč. 9, č. 6 (2014), s. 1-11 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 Keywords : Toxoplasma gondii * reproductive fitness * DNA methylation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.234, year: 2014

Low titer of antibody against Toxoplasma gondii may be related to resistant to cancer

OpenAIRE

Maryam Sharafi Seyedeh; Salehi Nahid; Mortazavi Nahid; Danesh Pour Shima; Yousefi Morteza; Yousofi Darani Hossein

2015-01-01

Context: Toxoplasma gondii is a protozoan parasite with a world-wide distribution. However, the majority of infected cases remain symptomless. There are raising scientific evidences indicating that parasitic infections induce antitumor activity against certain types of cancers. The inhibitory effect of T. gondii on cancer growth has also been shown in cell culture and mouse model. Aims: Considering the anti-tumor effect of this parasite, in this study the relationship between low titer of ...

Concentration and retention of Toxoplasma gondii oocysts by marine snails demonstrate a novel mechanism for transmission of terrestrial zoonotic pathogens in coastal ecosystems

Science.gov (United States)

Krusor, Colin; Smith, Woutrina A.; Tinker, M. Tim; Silver, Mary; Conrad, Patricia A.; Shapiro, Karen

2015-01-01

The parasite Toxoplasma gondii is an environmentally persistent pathogen that can cause fatal disease in humans, terrestrial warm-blooded animals and aquatic mammals. Although an association between T. gondii exposure and prey specialization on marine snails was identified in threatened California sea otters, the ability of kelp-dwelling snails to transmit terrestrially derived pathogens has not been previously investigated. The objective of this study was to measure concentration and retention of T. gondii by marine snails in laboratory aquaria, and to test for natural T. gondii contamination in field-collected snails. Following exposure to T. gondii-containing seawater, oocysts were detected by microscopy in snail faeces and tissues for 10 and 3 days respectively. Nested polymerase chain reaction was also applied as a method for confirming putative T. gondii oocysts detected in snail faeces and tissues by microscopy. Toxoplasma gondiiwas not detected in field-collected snails. Results suggest that turban snails are competent transport hosts for T. gondii. By concentrating oocysts in faecal pellets, snails may facilitate entry of T. gondii into the nearshore marine food web. This novel mechanism also represents a general pathway by which marine transmission of terrestrially derived microorganisms can be mediated via pathogen concentration and retention by benthic invertebrates.

A new set of primers for the detection of Toxoplasma gondii in amniotic fluid using polymerase chain reaction.

Science.gov (United States)

Pelloux, H; Weiss, J; Simon, J; Muet, F; Fricker-Hidalgo, H; Goullier-Fleuret, A; Ambroise-Thomas, P

1996-04-15

A new PCR system including a pair of primers, a probe and an internal control were designed from the B1 gene of Toxoplasma gondii. The system described allowed the detection of less than 10 tachyzoites of the RH strain of T. gondii. Among 21 amniotic fluid samples, this system diagnosed the cases of congenital toxoplasmosis which were simultaneously diagnosed using mice inoculation, in vitro culture, and serology from both amniotic fluid and fetal blood. These results show that these new primers allow for a highly sensitive detection of T. gondii DNA.

97 original article toxoplasma gondii infection in hiv/aids: prevalence

African Journals Online (AJOL)

Keywords: Toxoplasma gondii , IgG, Seroprevalence, HIV positive, CD4 cells. ... with immunosuppressive cancer and transplant ... due to active parasitaemia during pregnancy can .... especially in the night where they look for leftover.

Prevalence of Toxoplasma gondii in small mammals from the Ardennes region, France.

Science.gov (United States)

Afonso, Eve; Poulle, Marie-Lazarine; Lemoine, Mélissa; Villena, Isabelle; Aubert, Dominique; Gilot-Fromont, Emmanuelle

2007-11-01

Serum samples from 218 small mammals trapped in forest and grassland in the Ardennes region (North-eastern France) were tested for antibodies to Toxoplasma gondii. Using the modified agglutination test, positive results were found in 4/92 Apodemus sp., 3/64 Clethrionomys glareolus, 0/26 Microtus agrestis, 0/4 Micromys minutus, 3/5 Sorex sp., 2/9 Arvicola terrestris, and 7/18 Talpa europaea. Toxoplasma gondii was not isolated from the heart of seropositive individuals after bioassay in mice. Seroprevalence was significantly higher in large fossorial mammals living in grassland than in small forest mammals, probably related to ecological factors.

Toxoplasma gondii: prevalence and characterization of new genotypes in free-range chickens from south Brazil.

Science.gov (United States)

Vieira, Fernando Emmanuel Gonçalves; Sasse, João Pedro; Minutti, Ana Flávia; Miura, Ana Carolina; de Barros, Luiz Daniel; Cardim, Sergio Tosi; Martins, Thais Agostinho; de Seixas, Mércia; Yamamura, Milton Issashi; Su, Chunlei; Garcia, João Luis

2018-03-01

Toxoplasma gondii is an intracellular parasite that can infect all warm-blooded animals including humans. Recent studies showed that T. gondii strains from South America are genetically diverse. The present work aimed to determine T. gondii prevalence in free-ranging chicken in northwest Parana state in Brazil by two serological tests, to isolate the parasites from seropositive chickens and to genotype the isolates. Antibodies to T. gondii in 386 serum samples from 24 farms were investigated by immunofluorescence antibody assay (IFA) and modified agglutination test (MAT). Samples having titers ≥ 16 were considered positive for both tests. Among the 386 serum samples, 102 (26.4%) were positive for IFA, 64 (16.6%) were positive for MAT, 47 (12.2%) were positive in both tests, and 119 (30.8%) were positive in at least one of the two tests. Brain and pool of heart, lung, and liver from the 119 seropositive chickens were used for mouse bioassay to isolate the parasites. Thirty eight (31.9%) of these seropositive chickens were considered positives in mouse bioassay and 18 isolates were obtained. The isolates were characterized by 10 PCR-RFLP genetic markers including SAG1, SAG2 (5'-3'SAG2, alt.SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. Results of genotyping were compared with the genotypes in ToxoDB database. It revealed ten genotypes, including ToxoDB PCR-RFLP genotypes #6 (n = 2), #19 (n = 1), #21 (n = 2), #111 (n = 2), #152 (n = 1), and #175 (n = 1) and four new types not described before. Our results confirmed a high genetic diversity of this parasite in southern Brazil and also showed that the use of two serological tests in combination can improve the chance of T. gondii isolation. More studies should be taken to determine the zoonotic potential of chickens in the transmission of T. gondii.

Latitudinal variability in the seroprevalence of antibodies against Toxoplasma gondii in non-migrant and Arctic migratory geese

NARCIS (Netherlands)

Sandstrom, Cecilia A. M.; Buma, Anita G. J.; Hoye, Bethany J.; Prop, Jouke; van der Jeugd, Henk; Voslamber, Berend; Madsen, Jesper; Loonen, Maarten J. J. E.

2013-01-01

Toxoplasma gondii is an intracellular coccidian parasite found worldwide and is known to infect virtually all warm-blooded animals. It requires a cat (family Felidae) to complete its full life cycle. Despite the absence of wild felids on the Arctic archipelago of Svalbard, T. gondii has been found

Toxoplasma gondii infection induces suppression in a mouse model of allergic airway inflammation.

Directory of Open Access Journals (Sweden)

Ignacio M Fenoy

Full Text Available Allergic asthma is an inflammatory disorder characterized by infiltration of the airway wall with inflammatory cells driven mostly by activation of Th2-lymphocytes, eosinophils and mast cells. There is a link between increased allergy and a reduction of some infections in Western countries. Epidemiological data also show that respiratory allergy is less frequent in people exposed to orofecal and foodborne microbes such as Toxoplasma gondii. We previously showed that both acute and chronic parasite T. gondii infection substantially blocked development of airway inflammation in adult BALB/c mice. Based on the high levels of IFN-γ along with the reduction of Th2 phenotype, we hypothesized that the protective effect might be related to the strong Th1 immune response elicited against the parasite. However, other mechanisms could also be implicated. The possibility that regulatory T cells inhibit allergic diseases has received growing support from both animal and human studies. Here we investigated the cellular mechanisms involved in T. gondii induced protection against allergy. Our results show for the first time that thoracic lymph node cells from mice sensitized during chronic T. gondii infection have suppressor activity. Suppression was detected both in vitro, on allergen specific T cell proliferation and in vivo, on allergic lung inflammation after adoptive transference from infected/sensitized mice to previously sensitized animals. This ability was found to be contact-independent and correlated with high levels of TGF-β and CD4(+FoxP3(+ cells.

Chronic Toxoplasma gondii in Nurr1-Null Heterozygous Mice Exacerbates Elevated Open Field Activity

OpenAIRE

Eells, Jeffrey B.; Varela-Stokes, Andrea; Guo-Ross, Shirley X.; Kummari, Evangel; Smith, Holly M.; Cox, Erin; Lindsay, David S.

2015-01-01

Latent infection with Toxoplasma gondii is common in humans (approximately 30% of the global population) and is a significant risk factor for schizophrenia. Since prevalence of T. gondii infection is far greater than prevalence of schizophrenia (0.5-1%), genetic risk factors are likely also necessary to contribute to schizophrenia. To test this concept in an animal model, Nurr1-null heterozygous (+/-) mice and wild-type (+/+) mice were evaluate using an emergence test, activity in an open fie...

Occurrence of infection by Toxoplasma gondii in slaughtered swine in the northwestern region of Paraná, Brazil

Directory of Open Access Journals (Sweden)

Hannah Lia Ettiene Peruch Lemos dos Santos

2015-07-01

Full Text Available This study aimed to determine the prevalence of Toxoplasma gondii in swine slaughtered in Iporã, Northwest Paraná state. Blood samples were obtained from 500 finishing swine. All animals were raised under intensive farming; the blood samples were analyzed using the immunofluorescence antibody test (IFAT. Animals with titers of ?64 were considered positive for T. gondii infection. Of the tested samples, 63 (12.6% were positive by IFAT; 58 (92.06% of these showed titers of 64 (4.7%, with titers 256 and two (3.1% titers of 1024. These pigs might be considered a source of T. gondii infection for humans

Mast cell activator compound 48/40 is not an effective adjuvant for UV-attenuated Toxoplasma gondii vaccine.

Science.gov (United States)

Li, Xi; Chen, Shengjie; Huang, Shiguang; Lu, Fangli

2017-08-01

Toxoplasma gondii (T. gondii, Tg) is a globally distributed parasitic protozoan causing different forms of toxoplasmosis in humans. Mast cells (MCs) play a role during T. gondii infection. Several studies suggest that MC activator compound 48/80 (C48/80) may be an effective vaccine adjuvant resulting in a potent and protective antigen-specific immune response against bacteria or virus infections. The present study was performed to determine whether C48/80 had adjuvant activity for ultraviolet (UV)-attenuated T. gondii vaccine to induce protective immune responses against T. gondii in mouse model. Kunming mice were divided into the following groups: naive mice, naive mice administrated with C48/80 intraperitoneal (i.p.) injection, mice infected by i.p. injection of 10 4 T. gondii RH strain alone (Tg group), mice infected with 10 4 RH tachyzoites plus C48/80 administration (Tg + C48/80), mice immunized with UV-Tg alone, and mice immunized with UV-Tg plus C48/80 administration (UV-Tg + C48/80). All the vaccinated mice were challenged with 10 4 tachyzoites of T. gondii RH strain at the same time as the primary infection. The survival rates, liver histopathologies, liver parasite burdens, and mRNA expression levels of Th1 and Th2 cytokines in the livers and spleens detected by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) were compared among the aforementioned groups after primary infection or challenge infection. The results showed that, compared to the Tg group or Tg + C48/80 group, the UV-Tg + Tg group and UV-Tg + C48/80 + Tg group had significantly prolonged survival time, lower liver histopathological scores, decreased liver parasite burdens, and increased levels of Th1 and Th2 cytokines in the livers and spleens. There was no significant difference of survival time between the UV-Tg + Tg group and the UV-Tg + C48/80 + Tg group; however, the UV-Tg + C48/80 + Tg group showed higher parasite burden, more severe

A systematic review and meta-analysis of the seroprevalence of Toxoplasma gondii in cats in mainland China.

Science.gov (United States)

Ding, Huan; Gao, Yu-Meng; Deng, Yao; Lamberton, Poppy H L; Lu, Da-Bing

2017-01-13

Toxoplasmosis is caused by Toxoplasma gondii which can infect all warm-blooded animals. As the most common feline definitive host, cats play a vital role in the transmission of T. gondii. However, national estimates of the seroprevalence of T. gondii in cats in mainland China are lacking, and therefore a systematic review and meta-analysis were performed to provide insight into national environmental transmission levels and potential transmission to humans. Studies published up until July 1, 2016, on T. gondii seroprevalence in cats within mainland China were searched for in CNKI, WanFang, CBM, PubMed, Embase and through the reference lists of resulting articles. The seroprevalence with its 95% confidence interval (CI) for each individual study was presented, and then point estimates and their 95% confidence intervals (CIs) of pooled seroprevalence were calculated. Subgroup analyses were performed according to potential risk factors. A total of 38 eligible studies, published between 1995 to 2016, covering fifteen provinces and municipalities, and involving 7,285 cats, were included. The seroprevalence in cats per study ranged from 3.9 to 79.4% with a median of 20.3%. As substantial heterogeneity existed among studies, a random-effects model was used to estimate the pooled seroprevalence. The value of the point estimate seroprevalence was 24.5% (95% CI: 20.1-29.0). Seroprevalence in stray cats was significantly higher than in pet cats (OR = 3.00, 95% CI: 1.60-5.64). The seroprevalence increased significantly with cat age (P = 0.018) with 17.4% (95% CI: 7.6-27.2) in the group of ≤ 1 year old, 19.5% (95% CI: 12.7-26.3) in the group of ≤ 3 year-old and 31.6% (95% CI: 22.9-40.3) in the group of > 3 year-old. The seroprevalence of T. gondii in cats in mainland China was moderate and was associated with cat ownership and age. Due to the increasing prevalence of pet cats in China and the intimate relationship between these cats and humans, this

Development of an activity-based probe for acyl-protein thioesterases

Science.gov (United States)

Garland, Megan; Schulze, Christopher J.; Foe, Ian T.; van der Linden, Wouter A.; Child, Matthew A.

2018-01-01

Protein palmitoylation is a dynamic post-translational modification (PTM) important for cellular functions such as protein stability, trafficking, localization, and protein-protein interactions. S-palmitoylation occurs via the addition of palmitate to cysteine residues via a thioester linkage, catalyzed by palmitoyl acyl transferases (PATs), with removal of the palmitate catalyzed by acyl protein thioesterases (APTs) and palmitoyl-protein thioesterases (PPTs). Tools that target the regulators of palmitoylation–PATs, APTs and PPTs–will improve understanding of this essential PTM. Here, we describe the synthesis and application of a cell-permeable activity-based probe (ABP) that targets APTs in intact mammalian cells and the parasite Toxoplasma gondii. Using a focused library of substituted chloroisocoumarins, we identified a probe scaffold with nanomolar affinity for human APTs (HsAPT1 and HsAPT2) and synthesized a fluorescent ABP, JCP174-BODIPY TMR (JCP174-BT). We use JCP174-BT to profile HsAPT activity in situ in mammalian cells, to detect an APT in T. gondii (TgPPT1). We show discordance between HsAPT activity levels and total protein concentration in some cell lines, indicating that total protein levels may not be representative of APT activity in complex systems, highlighting the utility of this probe. PMID:29364904

Immunological response and protection of mice immunized with plasmid encoding Toxoplasma gondii glycolytic enzyme malate dehydrogenase.

Science.gov (United States)

Hassan, I A; Wang, S; Xu, L; Yan, R; Song, X; XiangRui, L

2014-12-01

Toxoplasma gondii Malate dehydrogenase (TgMDH) plays an important role as part of the energy production cycle. In this investigation, immunological changes and protection efficiency of this protein delivered as a DNA vaccine have been evaluated. Mice were intramuscularly immunized with pTgMDH, followed by challenge with virulent T. gondii RH strain, 2 weeks after the booster immunization. Compared to the control groups, the results showed that pTgMDH has stimulated specific humoral response as demonstrated by significant high titers of total IgG and subclasses IgG1 and IgG2a , beside IgA and IgM, but not IgE. Analysis of cytokine profiles revealed significant increases of IFN-γ, IL-4 and IL-17, while no significant changes were detected in TGF-β1. In cell-mediated response, both T lymphocytes subpopulations CD4(+) and CD8(+) were positively recruited as significant percentages were recorded in response to immunization with TgMDH. Significant long survival rate, 17 days, has been observed in the TgMDH vaccinated group, in contrast with control groups which died within 8-9 days after challenge. These results demonstrated that TgMDH could induce significant immunological responses leading to a considerable level of protection against acute toxoplasmosis infection. © 2014 John Wiley & Sons Ltd.

Polyparasitism Is Associated with Increased Disease Severity in Toxoplasma gondii-Infected Marine Sentinel Species

Science.gov (United States)

Gibson, Amanda K.; Raverty, Stephen; Lambourn, Dyanna M.; Huggins, Jessica; Magargal, Spencer L.; Grigg, Michael E.

2011-01-01

In 1995, one of the largest outbreaks of human toxoplasmosis occurred in the Pacific Northwest region of North America. Genetic typing identified a novel Toxoplasma gondii strain linked to the outbreak, in which a wide spectrum of human disease was observed. For this globally-distributed, water-borne zoonosis, strain type is one variable influencing disease, but the inability of strain type to consistently explain variations in disease severity suggests that parasite genotype alone does not determine the outcome of infection. We investigated polyparasitism (infection with multiple parasite species) as a modulator of disease severity by examining the association of concomitant infection of T. gondii and the related parasite Sarcocystis neurona with protozoal disease in wild marine mammals from the Pacific Northwest. These hosts ostensibly serve as sentinels for the detection of terrestrial parasites implicated in water-borne epidemics of humans and wildlife in this endemic region. Marine mammals (151 stranded and 10 healthy individuals) sampled over 6 years were assessed for protozoal infection using multi-locus PCR-DNA sequencing directly from host tissues. Genetic analyses uncovered a high prevalence and diversity of protozoa, with 147/161 (91%) of our sampled population infected. From 2004 to 2009, the relative frequency of S. neurona infections increased dramatically, surpassing that of T. gondii. The majority of T. gondii infections were by genotypes bearing Type I lineage alleles, though strain genotype was not associated with disease severity. Significantly, polyparasitism with S. neurona and T. gondii was common (42%) and was associated with higher mortality and more severe protozoal encephalitis. Our finding of widespread polyparasitism among marine mammals indicates pervasive contamination of waterways by zoonotic agents. Furthermore, the significant association of concomitant infection with mortality and protozoal encephalitis identifies polyparasitism as

Polyparasitism is associated with increased disease severity in Toxoplasma gondii-infected marine sentinel species.

Directory of Open Access Journals (Sweden)

Amanda K Gibson

2011-05-01

Full Text Available In 1995, one of the largest outbreaks of human toxoplasmosis occurred in the Pacific Northwest region of North America. Genetic typing identified a novel Toxoplasma gondii strain linked to the outbreak, in which a wide spectrum of human disease was observed. For this globally-distributed, water-borne zoonosis, strain type is one variable influencing disease, but the inability of strain type to consistently explain variations in disease severity suggests that parasite genotype alone does not determine the outcome of infection. We investigated polyparasitism (infection with multiple parasite species as a modulator of disease severity by examining the association of concomitant infection of T. gondii and the related parasite Sarcocystis neurona with protozoal disease in wild marine mammals from the Pacific Northwest. These hosts ostensibly serve as sentinels for the detection of terrestrial parasites implicated in water-borne epidemics of humans and wildlife in this endemic region. Marine mammals (151 stranded and 10 healthy individuals sampled over 6 years were assessed for protozoal infection using multi-locus PCR-DNA sequencing directly from host tissues. Genetic analyses uncovered a high prevalence and diversity of protozoa, with 147/161 (91% of our sampled population infected. From 2004 to 2009, the relative frequency of S. neurona infections increased dramatically, surpassing that of T. gondii. The majority of T. gondii infections were by genotypes bearing Type I lineage alleles, though strain genotype was not associated with disease severity. Significantly, polyparasitism with S. neurona and T. gondii was common (42% and was associated with higher mortality and more severe protozoal encephalitis. Our finding of widespread polyparasitism among marine mammals indicates pervasive contamination of waterways by zoonotic agents. Furthermore, the significant association of concomitant infection with mortality and protozoal encephalitis identifies

Titres of Specific Antibodies against Toxoplasma gondii in Goats and their Kids

Directory of Open Access Journals (Sweden)

Ľubica Mišurová

2009-01-01

Full Text Available The aim of our study was to perform repeated determination of specific antibody levels in mothers and their kids in order to assess indirectly the possibility of vertical transmission of toxoplasmosis in goats. Twenty-eight goats with their kids were included in the study. The following variables were assessed: number of born kids in relation to antibody titres of goats; levels of specific antibodies in the blood of goats and kids; and concentrations of immunoglobulins (Ig, total protein (TP and total globulins (G in order to define the end of colostral immunity and the start of active production of antibodies in kids under 69 days of age. Specific antibodies against Toxoplasma gondii in goats were detected by IFAT in titres ranging from 0 to 1 280. Out of a total of 28 animals, 5 goats were negative (17.9% and 23 goats were seropositive (82.1%. The goats delivered 42 kids. A total ratio of number of kids to number of mothers was 1.5. Partial evaluation of results in goats without positive titre against T. gondii before parturition and goats with positive titre showed that negative goats tended to have more kids (p p < 0.01 of monitored non-specific immunity indicators. During this period, we observed increased titres of specific antibodies against toxoplasmosis in 20 kids (5 kids 41 days old, 5 kids 55 days old, and 10 kids 69 days old and thus we could assume the possibility of vertical transmission of toxoplasmosis.

Soroprevalência de Toxoplasma gondii em rebanhos caprinos no Estado de São Paulo Seroprevalence of Toxoplasma gondii in dairy goats in the São Paulo State, Brazil

Directory of Open Access Journals (Sweden)

Rodrigo Soares Mainardi

2003-12-01

Full Text Available Foi colhido um total de 442 soros em rebanhos caprinos de sete regiões do Estado de São Paulo e testados para anticorpos contra Toxoplasma gondii pela reação de imunofluorescência indireta. Em todos os rebanhos, foram encontrados caprinos reagentes, totalizando 64 (14,5% animais com sorologia positiva em diferentes capris.Four hundred forty-two serum samples were collected from dairy goats in seven regions of São Paulo State. These were tested for Toxoplasma gondii antibodies using the indirect immunofluorescent antibody test. Sixty-four (14,5% serologically positive animals were found from all these goat farms studied.

Metabolic Cooperation of Glucose and Glutamine Is Essential for the Lytic Cycle of Obligate Intracellular Parasite Toxoplasma gondii.

Science.gov (United States)

Nitzsche, Richard; Zagoriy, Vyacheslav; Lucius, Richard; Gupta, Nishith

2016-01-01

Toxoplasma gondii is a widespread protozoan parasite infecting nearly all warm-blooded organisms. Asexual reproduction of the parasite within its host cells is achieved by consecutive lytic cycles, which necessitates biogenesis of significant energy and biomass. Here we show that glucose and glutamine are the two major physiologically important nutrients used for the synthesis of macromolecules (ATP, nucleic acid, proteins, and lipids) in T. gondii, and either of them is sufficient to ensure the parasite survival. The parasite can counteract genetic ablation of its glucose transporter by increasing the flux of glutamine-derived carbon through the tricarboxylic acid cycle and by concurrently activating gluconeogenesis, which guarantee a continued biogenesis of ATP and biomass for host-cell invasion and parasite replication, respectively. In accord, a pharmacological inhibition of glutaminolysis or oxidative phosphorylation arrests the lytic cycle of the glycolysis-deficient mutant, which is primarily a consequence of impaired invasion due to depletion of ATP. Unexpectedly, however, intracellular parasites continue to proliferate, albeit slower, notwithstanding a simultaneous deprivation of glucose and glutamine. A growth defect in the glycolysis-impaired mutant is caused by a compromised synthesis of lipids, which cannot be counterbalanced by glutamine but can be restored by acetate. Consistently, supplementation of parasite cultures with exogenous acetate can amend the lytic cycle of the glucose transport mutant. Such plasticity in the parasite's carbon flux enables a growth-and-survival trade-off in assorted nutrient milieus, which may underlie the promiscuous survival of T. gondii tachyzoites in diverse host cells. Our results also indicate a convergence of parasite metabolism with cancer cells. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by 60Co

International Nuclear Information System (INIS)

Costa, Andrea da

2013-01-01

Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

Acute onset of encephalomyelitis with atypical lesions associated with dual infection of Sarcocystis neurona and Toxoplasma gondii in a dog.

Science.gov (United States)

Gerhold, Richard; Newman, Shelley J; Grunenwald, Caroline M; Crews, Amanda; Hodshon, Amy; Su, Chunlei

2014-10-15

A two-year-old male, neutered, basset hound-beagle mix with progressive neurological impairment was examined postmortem. Grossly, the dog had multiple raised masses on the spinal cord between nerve roots. Microscopically, the dog had protozoal myeloencephalitis. Toxoplasma gondii and Sarcocystis neurona were detected in the CNS by immunohistochemistry and polymerase chain reaction (PCR). Sarcocysts in formalin-fixed muscle were negative for Sarcocystis by PCR. Banked serum was negative for T. gondii using the modified agglutination test, suggesting an acute case of T. gondii infection or immunosuppression; however, no predisposing immunosuppressive diseases, including canine distemper, were found. To the authors' knowledge, this is the first report of dual T. gondii and S. neurona infection in a dog. Published by Elsevier B.V.

Detection of Toxoplasma gondii in a free-ranging giant anteater

Directory of Open Access Journals (Sweden)

Thais Oliveira Morgado

Full Text Available ABSTRACT: Toxoplasmosis is caused by Toxoplasma gondii, an obligatory intracellular protozoan, which establishes acute and chronic infections in birds and mammals, including humans. This note reports, for the first time, the detection and sequencing of DNA from T. gondii in the peripheral blood of a young free range giant anteater (Myrmecophaga tridactyla. For the diagnosis, the following methods were used: polymerase chain reaction (PCR and positive serology (1:800 by means of the modified agglutination test (MAT. Since this species may be consumed by humans and predated by wild felids, its importance is emphasized as a probable source of zoonotic infection, in addition to its possible participation in the infection enzootic cycle. Although, parasitemia has been confirmed in this specimen, it presented no clinical sign of infection.

Comportamento imunológico e antigênico de cinco amostras de Toxoplasma gondii inoculadas em gatos Immunogenic and antigenic aspects from five Toxoplasma gondii strains inoculated in cats

Directory of Open Access Journals (Sweden)

Italmar Teodorico Navarro

1998-09-01

Full Text Available A biologia do Toxoplasma gondii demonstra que o gato é o hospedeiro completo, responsável pela disseminação do parasito. Assim, dois gatos domésticos foram imunizados com cada uma das amostras, VPS (humano, LIV-IV e LIV-V (suíno, CPL (caprino e CN (felino de T. gondii. Foram utilizados taquizoítas vivos em inóculos endovenosos de 2x10(6 (1° inóculo} e 4x10(7 (2° inóculo - 35 dias após, exceto a amostra VPS, onde 1 gato morreu no 10° dia com sinais clínicos agudos da doença, nas outras amostras, nenhum sinal clínico foi constatado durante os 6 meses de observação. O nível de anticorpos na imunização foi acompanhado através da reação de imunofluorescência indireta (IFI com conjugado anti-IgG de felino. Os títulos de anticorpos obtidos no 20° dia variaram de 1:1.024 a 1:4.096 e de 1:1.024 a 1:8.000 no 40° dia. Somente a amostra VPS expressou títulos de 1:16.000 no 30° dia da imunização. Títulos homólogos e heterólogos foram equivalentes sem nenhuma diferença entre as amostras. Quando soros imunes foram adsorvidos com taquizoítas vivos de cada amostra, a redução nos títulos de anticorpos foi demonstrada em ambos homólogos e heterólogos. Esses resultados sugerem que, embora diferente em virulência para gatos, a superfície antigênica é comum entre as amostras do T. gondii, com base no nível de anticorpo demonstrado pela IFI. Esses resultados também demonstram que, aparentemente, não há correlação entre virulência e as características sorológicas das amostras estudadas no T. gondii. Entretanto, a importância do teste IFI em diagnóstico laboratorial é reforçada.The biology of Toxoplasma gondii demonstrate that cats are the complete host responsable for the dissemination of this parasites. Two domestic cats were immunised with Toxoplasma gondii strains VPS (human, LIV-IV and LIV-V (porcine, CPL (caprine and CN (feline. Live tachyzoites were utilized in intravenous inoculation of 2x10(7 (first

Seroprevalence of antibody to TgGRA7 antigen of Toxoplasma gondii in livestock animals from Western Java, Indonesia.

Science.gov (United States)

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

2015-12-01

Toxoplasmosis is a concern in both human and veterinary medicine, and the consumption of undercooked meat infected with Toxoplasma gondii is a major risk factor in human infection. Establishing the prevalence of the parasite in food-producing livestock is essential to reduce the risk of human infection. This study aimed to determine the prevalence of T. gondii-specific antibodies in cattle and pigs in Western Java, Indonesia. Serum samples from 598 cattle and 205 pigs from 18 locations in Western Java, Indonesia, were tested for antibodies to T. gondii using an enzyme-linked immunosorbent assay (ELISA). The seroprevalence was 14.6% in pigs and 7.4% in cattle, and significantly more pigs were seropositive compared with cattle (p<0.01). The results of this study suggest that consumption of undercooked meat should be regarded as an important source of infection in people. This study suggests that the risk factors for T. gondii infection in livestock appeared to be different in each location because geographical variation in seroprevalence was observed. The results of this study will facilitate further research to identify and control risk factors for T. gondii in the surveyed locations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Group 1 innate lymphoid cells in Toxoplasma gondii infection.

Science.gov (United States)

Dunay, I R; Diefenbach, A

2018-02-01

Innate lymphoid cells (ILCs) are a group of lymphocytes that carry out important functions in immunity to infections and in organ homeostasis at epithelial barrier surfaces. ILCs are innate immune cells that provide an early source of cytokines to initiate immune responses against pathogens. Cytotoxic ILCs (i.e. conventional (c)NK cells) and several subsets of helper-like ILCs are the major branches of the ILC family. Conventional NK cells and group 1 ILCs share several characteristics such as surface receptors and the ability to produce IFN-γ upon activation, but they differ in their developmental paths and in their dependence on specific transcription factors. Infection of mice with the intracellular parasite Toxoplasma gondii is followed by a strong Th1-mediated immune response. Previous studies indicate that NK1.1 + cells contribute to the production of IFN-γ and TNF and cytotoxicity during acute T. gondii infection. Upon oral infection, the parasite infects intestinal enterocytes, and within the lamina propria, innate immune responses lead to initial parasite control although the infection disseminates widely and persists long-term in immune privileged sites despite adaptive immunity. Upon parasite entry into the small intestine, during the acute stage, ILC1 produce high levels of IFN-γ and TNF protecting barrier surfaces, thus essentially contributing to early parasite control. We will discuss here the role of innate lymphocytes during T. gondii infection in the context of the only recently appreciated diversity of ILC subsets. © 2018 John Wiley & Sons Ltd.

Molecular detection of Toxoplasma gondii infection in slaughtered ruminants (sheep, goats and cattle) in Northwest Tunisia.

Science.gov (United States)

Amdouni, Yosra; Rjeibi, Mohamed Ridha; Rouatbi, Mariem; Amairia, Safa; Awadi, Sofia; Gharbi, Mohamed

2017-11-01

The present study aimed to estimate the molecular prevalence of T. gondii infection in meat from slaughtered sheep, goats and cattle in Northwest Tunisia (Béja district). PCRs were performed on genomic DNA extracted from 420 meat samples (150 ewes, 120 goats and 150 cows). The overall molecular prevalence of T. gondii in sheep, goats and cattle were 33.3 (50/150), 32.5 (39/120) and 19.3% (29/150), respectively. Toxoplasma gondii molecular prevalences in the three meat ruminant species were significantly higher in adults compared to young animals (pgoats (pmeat. Extension programmes should be implemented to decrease the risk of infection related to sheep, goats and cattle meat manipulation and raw or undercooked meat consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antibodies to Toxoplasma gondii in Backyard and Roaming Pigs ...

African Journals Online (AJOL)

Toxoplasma gondii, the etiologic agent of Toxoplasmosis, can be transmitted to pigs through the ingestion of oocysts, and to humans through consumption of pork containing viable cysts causing neonatal deaths and abortion in animals, and opportunistic infections in immunocompromised humans. The objective of this ...

Comparison of Toxoplasma gondii IgG avidity Architect and Vidas assays with the estimated date of infection in pregnant women

Directory of Open Access Journals (Sweden)

Smets Aurélie

2016-01-01

Full Text Available A maternal Toxoplasma gondii infection during pregnancy is a risk for congenital infection through maternal-fetal transplacental transmission. Estimation of the date of infection is of the utmost importance for management and treatment recommendations. In this setting, IgG avidity has been shown to be useful as high avidity rules out an infection dating less than 4 months. The estimated date of infection can also be obtained by the ratio of T. gondii IgG titers measured by the Vidas (bioMérieux assay versus T. gondii IgG titers measured by the Architect (Abbott Laboratories test, together with T. gondii IgM and IgA antibody responses. In this study, using 117 serum samples from pregnant women, we compared the IgG avidity values obtained by Architect and Vidas with the presumed date of T. gondii infection established by the T. gondii IgG ratio of IgG Vidas and IgG Architect plus the IgM and IgA results. To date, IgG avidity Vidas seems to exhibit better performance than Architect. For both assays, gray zone results were most likely obtained from patients infected more than 4 months before sampling. These data should be taken into account for a possible reconsideration of the interpretation of avidity results in the gray zone.

Toxoplasma gondii seropositivity and co-infection with TORCH pathogens in high-risk patients from Qatar.

Science.gov (United States)

Abu-Madi, Marawan A; Behnke, Jerzy M; Dabritz, Haydee A

2010-04-01

Testing of patients who are deemed to be at high risk for TORCH pathogens, e.g., pregnant women, their fetuses, neonates, and acquired immunodeficiency syndrome (AIDS) patients, is important so that specific treatment can be initiated. This study included 1,857 such patients between 2005 and 2008. Logistic regression was used to evaluate factors associated with Toxoplasma gondii seropositivity. Among 823 women of childbearing age, 35.1% and 5.2% tested positive for T. gondii IgG and IgM, respectively. Three infants nationality, positive cytomegalovirus (CMV) and herpes simplex virus (HSV)-1 serostatus, and negative rubella IgG results. The decreasing prevalence of IgM antibodies between 2005 and 2008 suggested that exposure to T. gondii from food or environmental sources declined over this period in Qatar. Population-based studies of newborns would be helpful to accurately estimate incidence of congenital toxoplasmosis.

Toxoplasma gondii antibody prevalence and two new genotypes of the parasite in endangered Hawaiian Geese (nene: Branta sandvicensis)

Science.gov (United States)

Work, Thierry M.; Verma, Shiv K.; Su, Chunlei; Medeiros, John; Kaiakapu, Thomas; Kwok, Oliver C.; Dubey, Jitender P.

2016-01-01

Toxoplasma gondii is a protozoan parasite transmitted by domestic cats (Felis catus) that has historically caused mortality in native Hawaiian birds. To estimate how widespread exposure to the parasite is in nene (Hawaiian Geese, Branta sandvicensis), we did a serologic survey for T. gondii antibody and genetically characterized parasite DNA from the tissues of dead birds that had confirmed infections by immunohistochemistry. Of 94 geese sampled, prevalence on the island of Kauai, Maui, and Molokai was 21% (n=42), 23% (n=31), and 48% (n=21), respectively. Two new T. gondii genotypes were identified by PCR-restriction fragment length polymorphism from four geese, and these appeared segregated geographically. Exposure to T. gondii in wild nene is widespread and, while the parasite is not a major cause of death, it could have sublethal or behavioral effects. How to translate such information to implement effective ways to manage feral cats in Hawaii poses challenges.

Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic Forest, state of São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Solange Maria Gennari

Full Text Available Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and marsupials play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 48 marsupials, captured in the Atlantic Forest, São Paulo State, southeastern Brazil, were analyzed for the presence of T. gondii antibodies. Antibodies detected by the modified agglutination test (MAT ≥ 25 were found in 8.6% (13/151 of the rodents and 10.4% (5/48 of the marsupials, with titers ranging from 25 to 6400 and from 25 to 3200, respectively for the rodents and marsupials. Three of the eight species of rodents (Akodon spp., Oligoryzomys nigripesand Rattus norvegicus, and one from the four marsupial species (Didelphis aurita presented positive animals. T. gondii was described for the first time in the rodent Oligoryzomys nigripes.

Toxoplasma gondii seroprevalence in donkeys (Equus asinus) from the U.S.A. and isolation of T. gondii from cats on donkey farms

Science.gov (United States)

Donkeys (Equus asinus) are used as companion animals, in leisure activities as working animals, for onotherapy, and their meat and milk is used for human consumption in certain countries. Here we report first serological survey for Toxoplasma gondii in donkeys in the U.S.A. Serum samples were collec...

Infectivity of cysts of the ME-49 Toxoplasma gondii strain in bovine milk and homemade cheese

Directory of Open Access Journals (Sweden)

Hiramoto RM

2001-01-01

Full Text Available OBJECTIVE: Analyze the infectivity and storage resistance of cysts of the ME-49 strain of Toxoplasma gondii in artificially infected bovine milk and homemade fresh cheese. METHODS: Pasteurized bovine milk was infected with 10 cysts/ml of the ME-49 strain of T.gondii and inoculated in different groups of mice, immediately or after storage at 4ºC for 5, 10 and 20 days. Homemade fresh cheese was prepared with artificially infected milk, and also tested in groups of mice, using the same storage process. Infection was identified by the presence of cysts in the brain or serological testing in challenged mice after 5 weeks, confirmed by Western Blot and histology. RESULTS: The infectivity of cysts of the ME-49 strain of T.gondii was maintained in the milk even after storage for 20 days at refrigerator temperatures. Cysts were also able to survive the production process of homemade fresh cheese and storage for a period of 10 days in the same conditions. CONCLUSIONS: These data demonstrated that milk and dairy products could be an important source of T.gondii in human contamination, reinforcing the importance of milk pasteurization before any processing or ingestion.

First isolation and RFLP genotyping of Toxoplasma gondii from crab-eating fox (Cerdocyon thous-Linnaeus, 1766).

Science.gov (United States)

de Almeida, Jonatas Campos; de Melo, Renata Pimentel Bandeira; de Morais Pedrosa, Camila; da Silva Santos, Marcelo; de Barros, Luiz Daniel; Garcia, João Luis; Porto, Wagnner José Nascimento; Mota, Rinaldo Aparecido

2017-05-01

Wild animals may play an important role in the transmission and maintenance of Toxoplasma gondii in the environment. The purpose of the present study was to isolate and genotype T. gondii from a free-ranging crab-eating fox (Cerdocyon thous-Linnaeus, 1766). A crab-eating fox in critical health condition was attended in a veterinary hospital in Recife, Pernambuco State, Brazil. The animal died despite emergency treatment. The brain was collected aseptically and destined for mouse bioassay. One isolate of T. gondii was obtained, and Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) was used to assess genetic variability at 11 markers (SAG1, SAG2, altSAG2, SAG3, BTUB, GRA6, c228, c292, L358, PK1 and APICO). A murine model was used to assess the virulence of the isolate. Using the PCR-RFLP, genotype ToxoDB #13 was identified, which is considered an atypical strain. The isolate was classified as avirulent in the murine model. This is the first study to report T. gondii infection in the crab-eating fox. Copyright © 2017 Elsevier B.V. All rights reserved.

Occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chicken breeding in Northeast, Brazil

Directory of Open Access Journals (Sweden)

Marcela Fernanda Torres Samico Fernandes

2016-03-01

Full Text Available Abstract The aim of the present study was to investigate the occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chickens bred in the metropolitan area of Recife, Brazil. In total, 212 serum samples were collected from 16 properties, and 12 backyard chickens were collected in the six sanitary districts of Recife. An indirect immunofluorescence assay (IFA was used to investigate the occurrence of anti-Toxoplasma gondii antibodies. Polymerase chain reaction (PCR was used to detect T. gondii DNA in brain, heart, liver and lung specimens. Of the samples analyzed by serology, 86/212 (40.56% were positive; of the samples analyzed by PCR, 2/12 (16.7% were positive, with both samples positive by both tests (serological and molecular. The presence of antibody anti-T. gondii and parasite DNA in tissues of these animals are worrying aspects for public health because there is a risk of transmission of the parasite to humans through eating undercooked or raw meat. Based on the results, the adoption of preventive measures to prevent the cats access to the chickens creations should be encouraged, since these animals were identified in most of the studied properties.

Seroprevalence of Toxoplasma gondii infection in zoo and domestic animals in Jiangxi Province, China

Directory of Open Access Journals (Sweden)

Luo Houqiang

2017-01-01

Full Text Available Toxoplasma gondii is a zoonotic protozoan parasite that infects a wide range of warm-blooded animals throughout the world. In the present study, antibodies to T. gondii were determined using a commercial indirect hemagglutination (IHA test in wild animals in a zoo. Three of 11 giraffes (Giraffa camelopardalis (27%, 1 of 5 wolves (Canis lupus laniger (20%, 1 of 6 hippopotamuses (Hippopotamus amphibious (17%, and 2 of 9 tundra swans (Cygnus columbianus (22% were found to be positive. No antibodies were detected in leopards (Panthera pardus, wild geese (Anser cygnoides, and Eastern grey kangaroos (Macropus giganteus. Domestic species from 13 counties of Jiangxi Province, China were also investigated by an indirect hemagglutination (IHA test. Thirty-five of 340 goats (10%, 94 of 560 water buffaloes (17%, and 4 of 35 cattle (11% were found to be seropositive. This is the first report of T. gondii infection in animals kept in zoos and domestic animals in this province.

DNA chip-assisted diagnosis of a previously unknown etiology of intermediate uveitis- Toxoplasma gondii

Directory of Open Access Journals (Sweden)

Basu Soumyava

2010-01-01

Full Text Available We report the use of DNA chip technology in the identification of Toxoplasma gondii as the etiological agent in two patients with recurrent intermediate uveitis (IU. Both patients had recurrent episodes of vitritis (with no focal retinochoroidal lesion over varying time intervals and were diagnosed to have IU. The tuberculin test was negative in both. Blood counts, erythrocyte sedimentation rate, and serum angiotensin convertase enzyme levels were normal. In both cases, the vitreous fluid tested positive for the T. gondii DNA sequence by using a uveitis DNA chip (XCyton Pvt. Ltd., Bangalore, India. It contained complimentary sequences to "signature genes" of T. gondii, Mycobacterium tuberculosis, M. chelonae, and M. fortuitum. The enzyme-linked immunosorbent assay (ELISA detected elevated serum antitoxoplasma IgG levels in both. They responded to the antitoxoplasma therapy with oral co-trimoxazole (and additional intravitreal clindamycin in patient 1, with no recurrence during follow-ups of 6 and 8 months, respectively.

Toxoplasma gondii infection: seroprevalence and associated risk factors among primary schoolchildren in Lagos City, Southern Nigeria

Directory of Open Access Journals (Sweden)

Vincent Pam Gyang

2015-02-01

Full Text Available INTRODUCTION: Toxoplasma gondii infection has been described as the most widespread zoonotic infection of humans and other animals. Information concerning T. gondii infection among schoolchildren is unavailable in Lagos City, Nigeria. METHODS: This cross-sectional study investigated the seroprevalence and risk factors associated with T. gondii infection among primary schoolchildren (PSC from a community located in the center of Lagos, southern Nigeria, from November 2013 to March 2014. A total of 382 PSC were screened for the presence of sera anti-T. gondii antibodies using a latex agglutination test (TOXO Test-MT, Tokyo, Japan. A cutoff titer of ≥ 1:32 was considered positive, while titers ≥ 1:1,024 indicated high responders. Questionnaires were also used to obtain data on possible risk factors from parents/guardians. RESULTS: The overall seroprevalence was 24% (91/382, and 83.5% (76/91 of seropositive PSC were classified as high responders. Among the risk factors tested, including contact with cats and soil, consumption of raw meat and vegetables, and drinking unboiled water, none showed statistical significance after multivariate adjustment. No associations were observed among age, gender, body mass index (BMI, and parents' occupation/educational level. CONCLUSIONS: The findings in this study show evidence of active infection, and hence, there is need for urgent preventive measures in this city. Further investigation is required to clarify the transmission routes. Policy makers also need to initiate prevention and control programs to protect pregnant women and immunocompromised patients in particular because they are more severely affected by T. gondii infection.

Early diagnosis of congenital toxoplasmosis in newborn infants using IgG subclasses against two Toxoplasma gondii recombinant proteins

Directory of Open Access Journals (Sweden)

Carlos Henryque de Souza e Silva

2012-05-01

Full Text Available The aim of this work was to evaluate the utility of ELISA-based testing of total IgG (IgGt antibodies and its subclasses (IgG1, IgG2, IgG3 and IgG4 against soluble (STAg and recombinant (rSAG1 and rMIC3 antigens of Toxoplasma gondii for diagnosing congenital toxoplasmosis. Sera from 217 newborns initially testing positive for specific IgM in filter paper dried blood spots were tested for specific IgM and IgG by ELFA-VIDAS®. Congenital toxoplasmosis was confirmed in 175 and ruled out in 42 infants. The validity of the ELISA tests was determined using the persistence of IgG antibodies (ELFA-VIDAS® kit at the end of 12 months, which is considered the reference test for the diagnosis of congenital toxoplasmosis. The frequency of positivity with IgGt against STAg, rSAG1 and rMIC3 was found in 97.2%, 96.3% and 80.2%, respectively, of the newborns with confirmed congenital toxoplasmosis. IgG1 reacted with all three antigens, while IgG3 and IgG4 reacted preferentially with rMIC3. Higher mean values of reactivity (sample optical density/cut-off were found for all subclasses when using rMIC3. All of the antigens showed high sensitivity and low specificity in detecting anti-T. gondii IgGt and IgG1 and low sensitivity and high specificity in detecting IgG3 and IgG4. In conclusion, the combined detection of IgG antibody subclasses against recombinant toxoplasmic antigens may be useful for the early diagnosis of congenital toxoplasmosis.

Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta canadensis)

Science.gov (United States)

The protozoan Toxoplasma gondii infects virtually all warm-blooded animals, including birds, humans, livestock, and marine mammals. The consumption of raw or undercooked meat infected with T. gondii is considered an important source of infection in humans. Canada goose (Branta canadensis), the most ...

Comparative genomic sequence variation of Toxoplasma gondii reveals local admixture drives concerted expansion and diversification of secreted pathogenesis determinants

Science.gov (United States)

Toxoplasma gondii is among the most abundant parasites world-wide, infecting many wild and domestic animals and causing zoonotic infections in humans. T. gondii differs substantially in its distribution from closely related parasites that typically have narrow, specialized host ranges. We undertook...

Comparative sequence analysis of Toxoplasma gondii reveals local genomic admixture drives concerted expansion and diversification of secreted pathogenesis determinants

Science.gov (United States)

Toxoplasma gondii is among the most prevalent parasites worldwide, infecting many wild and domestic animals and causing zoonotic infections in humans. T. gondii differs substantially in its broad distribution from closely related parasites that typically have narrow, specialized host ranges. To un...

ACTIVATION OF T. GONDII INFECTION AFTER ALLOGENEIC TRANSPLANTATION OF HEMATOPOIETIC STEM CELLS: DEPENDENCE ON TIME OF TRANSPLANTATION AND SEROLOGICAL STATUS OF THE PATIENTS

Directory of Open Access Journals (Sweden)

A. B. Chukhlovin

2014-01-01

Full Text Available The article focuses on aspects of T. gondii reactivation/reinfection in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT. We have observed 297 patients who received conditioning therapy and allogeneic grafts due to different oncohematological or lymphoproliferative diseases (1 to 60 years old, at a mediane of 19 years. Conditioning regimens were either myeloablative (35%, or non-myeloablative (65%. DNA diagnostics of T. gondii was performed on a regular basis at 0 to 6 months post-HSCT. IgG and IgM antibodies against T. gondii were determined in 78 patients before HSCT, as well as in their donors. T. gondii DNA post-transplant proved to be positive in 13% of blood specimens, 9% of cerebrospinal liquor samples, 11% of bronchoalveolar cell lavages, and in 5% of urine sediments. In adolescent patients (10 to 14 years old, an increased prevalence of T. gondii was found in patients who received myeloablative treatment (p = 0.01. When assessing posttransplant dynamics of T. gondii, we have revealed distinct increase in the pathogen excretion within 1st month after HSCT (p = 0.03. Finally, initial presence of IgG antibodies against T. gondii in the patients was associated with lower incidence of the pathogen reactivation post-transplant.

Firocoxib on aqueous humor prostaglandin E 2 levels for controlling experimentally-induced breakdown of blood-aqueous barrier in healthy and Toxoplasma gondii -seropositive cats

Directory of Open Access Journals (Sweden)

Deise Cristine Schroder

2016-06-01

Full Text Available ABSTRACT: This study aimed to evaluate the effects of firocoxib for controlling experimentally-induced breakdown of the blood-aqueous barrier in healthy and Toxoplasma gondii -seropositive cats. Thirty two cats with no ocular abnormalities were used. Groups (n=8/each were formed with healthy cats that received 5mg g-1 of oral firocoxib (FH or no treatment (CH on day 0; seropositive cats for anti -T. gondii specific immunoglobulin G (IgG were grouped (n=8/each and treated in a similar fashion (FT and CT. On day 1, cats of all groups received the same treatment protocol, and 1h later, aqueocentesis was performed under general anesthesia (M0. Following 1h, the same procedure was repeated (M1. Quantitation of aqueous humor total protein and prostaglandin E2 (PGE2 were determined. Aqueous samples of seropositive cats were tested for anti- T. gondii specific IgG. In M0, aqueous samples of CT showed a significantly higher concentration of PGE2 in comparison with other groups (P<0.05. In all groups, PGE2 concentration increased significantly from M0 to M1 (P=0.001. PGE2 values did not change significantly between groups in M1 (P=0.17. Anti- T. gondii specific IgG were reported only in samples of M1, and aqueous titers did not change significantly between FT and CT (P=0.11. Although we have observed that aqueous humor PGE2 levels were significantly higher in cats of CT group during M0, such increase was not able to break the blood-aqueous barrier and cause anterior uveitis. Firocoxib did not prevent intraocular inflammation after aqueocentesis, in healthy and toxoplasmosis-seropositive cats.

Dual congenital transmission of Toxoplasma gondii and Sarcocystis neurona in a late-term aborted pup from a chronically infected southern sea otter (Enhydra lutris nereis).

Science.gov (United States)

Shapiro, Karen; Miller, Melissa A; Packham, Andrea E; Aguilar, Beatriz; Conrad, Patricia A; Vanwormer, Elizabeth; Murray, Michael J

2016-03-01

Toxoplasma gondii and Sarcocystis neurona are protozoan parasites with terrestrial definitive hosts, and both pathogens can cause fatal disease in a wide range of marine animals. Close monitoring of threatened southern sea otters (Enhydra lutris nereis) in California allowed for the diagnosis of dual transplacental transmission of T. gondii and S. neurona in a wild female otter that was chronically infected with both parasites. Congenital infection resulted in late-term abortion due to disseminated toxoplasmosis. Toxoplasma gondii and S. neurona DNA was amplified from placental tissue culture, as well as from fetal lung tissue. Molecular characterization of T. gondii revealed a Type X genotype in isolates derived from placenta and fetal brain, as well as in all tested fetal organs (brain, lung, spleen, liver and thymus). This report provides the first evidence for transplacental transmission of T. gondii in a chronically infected wild sea otter, and the first molecular and immunohistochemical confirmation of concurrent transplacental transmission of T. gondii and S. neurona in any species. Repeated fetal and/or neonatal losses in the sea otter dam also suggested that T. gondii has the potential to reduce fecundity in chronically infected marine mammals through parasite recrudescence and repeated fetal infection.

Comparison of Toxoplasma gondii Seroprevalence in Shelter Cats and Dogs during 1999-2001 and 2009-2011 in Tokyo, Japan.

Directory of Open Access Journals (Sweden)

Masaaki Oi

Full Text Available Toxoplasma gondii is an important human health concern with respect to abortion, congenital hydrocephalus, and encephalitis in immunocompromised people. Cats and dogs both are potential sources of T. gondii because they have close contact with humans. However, no epidemiological surveys have been conducted in Tokyo over the past decade. Therefore, the present study investigated and compared the seroprevalence of T. gondii infection in shelter cats and dogs during 1999-2001 and 2009-2011 in Tokyo, Japan. Serum samples were collected from 337 shelter cats and 325 shelter dogs in urban and suburban areas of Tokyo, during 1999-2001 (233 cats and 219 dogs and 2009-2011 (104 cats and 106 dogs. T. gondii antibodies were measured in the serum samples using a commercial latex agglutination test. Data were compared using the Fisher's exact test, and significance was indicated at P < 0.05. The overall seroprevalence of T. gondii infection in cats was 5.6% (13 of 233 in 1999-2001 and 6.7% (7 of 104 in 2009-2011, and that in dogs was 1.8% (4 of 219 and 1.9% (2 of 106, respectively. Significantly higher seroprevalence was observed in cats from suburban areas compared with cats in urban areas during both periods (P < 0.05. These results reveal that there has been little change in the feline and canine seroprevalence over the past decade, indicating that the risk of T. gondii exposure for cats and dogs in Tokyo is considerably low as the seroprevalence has reached a steady state.

Organizational changes of the daughter basal complex during the parasite replication of Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Ke Hu

2008-01-01

Full Text Available The apicomplexans are a large group of parasitic protozoa, many of which are important human and animal pathogens, including Plasmodium falciparum and Toxoplasma gondii. These parasites cause disease only when they replicate, and their replication is critically dependent on the proper assembly of the parasite cytoskeletons during cell division. In addition to their importance in pathogenesis, the apicomplexan parasite cytoskeletons are spectacular structures. Therefore, understanding the cytoskeletal biogenesis of these parasites is important not only for parasitology but also of general interest to broader cell biology. Previously, we found that the basal end of T. gondii contains a novel cytoskeletal assembly, the basal complex, a cytoskeletal compartment constructed in concert with the daughter cortical cytoskeleton during cell division. This study focuses on key events during the biogenesis of the basal complex using high resolution light microscopy, and reveals that daughter basal complexes are established around the duplicated centrioles independently of the structural integrity of the daughter cortical cytoskeleton, and that they are dynamic "caps" at the growing ends of the daughters. Compartmentation and polarization of the basal complex is first revealed at a late stage of cell division upon the recruitment of an EF-hand containing calcium binding protein, TgCentrin2. This correlates with the constriction of the basal complex, a process that can be artificially induced by increasing cellular calcium concentration. The basal complex is therefore likely to be a new kind of centrin-based contractile apparatus.

Isolation and Genetic Characterization of Toxoplasma gondii from Black Bears (Ursus americanus), Bobcats (Lynx rufus), and Feral Cats (Felis catus) from Pennsylvania.

Science.gov (United States)

Dubey, Jitender P; Verma, Shiv K; Calero-Bernal, Rafael; Cassinelli, Ana B; Kwok, Oliver C H; Van Why, Kyle; Su, Chunlei; Humphreys, Jan G

2015-01-01

Toxoplasma gondii infects virtually all warm-blooded hosts worldwide. Recently, attention has been focused on the genetic diversity of the parasite to explain its pathogenicity in different hosts. It has been hypothesized that interaction between feral and domestic cycles of T. gondii may increase unusual genotypes in domestic cats and facilitate transmission of potentially more pathogenic genotypes to humans, domestic animals, and wildlife. In the present study, we tested black bear (Ursus americanus), bobcat (Lynx rufus), and feral cat (Felis catus) from the state of Pennsylvania for T. gondii infection. Antibodies to T. gondii were found in 32 (84.2%) of 38 bears, both bobcats, and 2 of 3 feral cats tested by the modified agglutination test (cut off titer 1:25). Hearts from seropositive animals were bioassayed in mice, and viable T. gondii was isolated from 3 of 32 bears, 2 of 2 bobcats, and 2 of 3 feral cats. DNA isolated from culture-derived tachyzoites of these isolates was characterized using multilocus PCR-RFLP markers. Three genotypes were revealed, including ToxoDB PCR-RFLP genotype #1 or #3 (Type II, 1 isolate), #5 (Type 12, 3 isolates), and #216 (3 isolates), adding to the evidence of genetic diversity of T. gondii in wildlife in Pennsylvania. Pathogenicity of 3 T. gondii isolates (all #216, 1 from bear, and 2 from feral cat) was determined in outbred Swiss Webster mice; all three were virulent causing 100% mortality. Results indicated that highly mouse pathogenic strains of T. gondii are circulating in wildlife, and these strains may pose risk to infect human through consuming of game meat. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Toxoplasma gondii influences aversive behaviors of female rats in an estrus cycle dependent manner.

Science.gov (United States)

Golcu, Doruk; Gebre, Rahiwa Z; Sapolsky, Robert M

2014-08-01

The protozoan Toxoplasma gondii (T. gondii) manipulates the behavior of its rodent intermediate host to facilitate its passage to its feline definitive host. This is accomplished by a reduction of the aversive response that rodents show towards cat odors, which likely increases the predation risk. Females on average show similar changes as males. However, behaviors that relate to aversion and attraction are usually strongly influenced by the estrus cycle. In this study, we replicated behavioral effects of T. gondii in female rats, as well as expanded it to two novel behavioral paradigms. We also characterized the role of the estrus cycle in the behavioral effects of T. gondii on female rats. Uninfected females preferred to spend more time in proximity to rabbit rather than bobcat urine, and in a dark chamber rather than a lit chamber. Infected females lost both of these preferences, and also spent more time investigating social novelty (foreign bedding in their environment). Taken together, these data suggest that infection makes females less risk averse and more exploratory. Furthermore, this effect was influenced by the estrus cycle. Uninfected rats preferred rabbit urine to bobcat urine throughout the cycle except at estrus and metestrus. In contrast, infected rats lost this preference at every stage of the cycle except estrus. Commensurate with the possibility that this was a hormone-dependent effect, infected rats had elevated levels of circulating progesterone, a known anxiolytic. Copyright © 2014 Elsevier Inc. All rights reserved.

Seroprevalence and risk factors for Toxoplasma gondii infection on pig farms in central China.

Science.gov (United States)

Tao, Qing; Wang, Zhengsong; Feng, Huihui; Fang, Rui; Nie, Hao; Hu, Min; Zhou, Yanqin; Zhao, Junlong

2011-04-01

Toxoplasma gondii is a protozoan parasite that causes severe diseases in mammals, including humans, around the world. In China, pork is the main meat source; accordingly, T. gondii in pigs is considered an important source for human toxoplasmosis. Understanding the epidemiology of toxoplasmosis in pig farms is thus important for control of the disease in humans. The purpose of the present study was to investigate the epizootiology of T. gondii infections in pig farms in central China by assessing the seroprevalence and risk factors of this disease. In the present study, 3,558 sera samples were collected from pigs in 37 large-scale pig farms in this region and tested by AG-ELISA. The total seroprevalence was 24.5%, with the greatest prevalence in breeding pigs. The risk factors for toxoplasmosis suggest that high frequency of the contact of pigs with cats (P ≤ 0.01; IC 95%), high density of pig breeding (P ≤ 0.01; IC 95%), the presence of mosquitoes and flies (P ≤ 0.01; IC 95%), semi-patency pens (P ≤ 0.05; IC 95%), and low frequency of scavenging (P ≤ 0.01; IC 95%) were all associated with seroprevalence. In addition, the use of sulfonamides (P ≤ 0.01; IC 95%) significantly decreased seroprevalence. This is the first report of anti- T. gondii antibodies in pigs on large-scale pig farms in central China. The findings will provide useful information for designing control strategies of toxoplasmasis in pig farms.

A new pathogen transmission mechanism in the ocean: the case of sea otter exposure to the land-parasite Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Fernanda F M Mazzillo

Full Text Available Toxoplasma gondii is a land-derived parasite that infects humans and marine mammals. Infections are a significant cause of mortality for endangered southern sea otters (Enhydra lutris nereis, but the transmission mechanism is poorly understood. Otter exposure to T. gondii has been linked to the consumption of marine turban snails in kelp (Macrocystis pyrifera forests. It is unknown how turban snails acquire oocysts, as snails scrape food particles attached to surfaces, whereas T. gondii oocysts enter kelp beds as suspended particles via runoff. We hypothesized that waterborne T. gondii oocysts attach to kelp surfaces when encountering exopolymer substances (EPS forming the sticky matrix of biofilms on kelp, and thus become available to snails. Results of a dietary composition analysis of field-collected snails and of kelp biofilm indicate that snails graze the dense kelp-biofilm assemblage composed of pennate diatoms and bacteria inserted within the EPS gel-like matrix. To test whether oocysts attach to kelp blades via EPS, we designed a laboratory experiment simulating the kelp forest canopy in tanks spiked with T. gondii surrogate microspheres and controlled for EPS and transparent exopolymer particles (TEP - the particulate form of EPS. On average, 19% and 31% of surrogates were detected attached to kelp surfaces covered with EPS in unfiltered and filtered seawater treatments, respectively. The presence of TEP in the seawater did not increase surrogate attachment. These findings support a novel transport mechanism of T. gondii oocysts: as oocysts enter the kelp forest canopy, a portion adheres to the sticky kelp biofilms. Snails grazing this biofilm encounter oocysts as 'bycatch' and thereby deliver the parasite to sea otters that prey upon snails. This novel mechanism can have health implications beyond T. gondii and otters, as a similar route of pathogen transmission may be implicated with other waterborne pathogens to marine wildlife and

Negative serosurvey of Toxoplasma gondii antibodies in Golden-headed Lion Tamarin (Leontopithecus chrysomelas from Niterói/RJ, Brazil

Directory of Open Access Journals (Sweden)

Camila Vieira Molina

Full Text Available Abstract New World Nonhuman Primates are highly susceptible to clinical toxoplasmosis. Serum samples from 126 recently captured Leontopithecus chrysomelas, from an exotic and invasive population, were tested for Toxoplasma gondii antibodies by the modified agglutination test (MAT, cut-off 1:25; all were seronegative. The MAT is highly specific and is not species-specific. This is the first report of T. gondii survey in this tamarin in the wild. This result is consistent with prior reports that showed the high susceptibility of the species to infection by T. gondii usually with high mortality rates.

Qualitative Assessment for Toxoplasma gondii Exposure Risk Associated with Meat Products in the United States.

Science.gov (United States)

Guo, Miao; Buchanan, Robert L; Dubey, Jitender P; Hill, Dolores E; Lambertini, Elisabetta; Ying, Yuqing; Gamble, H Ray; Jones, Jeffrey L; Pradhan, Abani K

2015-12-01

Toxoplasma gondii is a global protozoan parasite capable of infecting most warm-blooded animals. Although healthy adult humans generally have no symptoms, severe illness does occur in certain groups, including congenitally infected fetuses and newborns, immunocompromised individuals including transplant patients. Epidemiological studies have demonstrated that consumption of raw or undercooked meat products is one of the major sources of infection with T. gondii. The goal of this study was to develop a framework to qualitatively estimate the exposure risk to T. gondii from various meat products consumed in the United States. Risk estimates of various meats were analyzed by a farm-to-retail qualitative assessment that included evaluation of farm, abattoir, storage and transportation, meat processing, packaging, and retail modules. It was found that exposure risks associated with meats from free-range chickens, nonconfinement-raised pigs, goats, and lamb are higher than those from confinement-raised pigs, cattle, and caged chickens. For fresh meat products, risk at the retail level was similar to that at the farm level unless meats had been frozen or moisture enhanced. Our results showed that meat processing, such as salting, freezing, commercial hot air drying, long fermentation times, hot smoking, and cooking, are able to reduce T. gondii levels in meat products. whereas nitrite and/or nitrate, spice, low pH, and cold storage have no effect on the viability of T. gondii tissue cysts. Raw-fermented sausage, cured raw meat, meat that is not hot-air dried, and fresh processed meat were associated with higher exposure risks compared with cooked meat and frozen meat. This study provides a reference for meat management control programs to determine critical control points and serves as the foundation for future quantitative risk assessments.

The Rhoptry Proteins ROP18 and ROP5 Mediate Toxoplasma gondii Evasion of the Murine, But Not the Human, Interferon-Gamma Response

Science.gov (United States)

Niedelman, Wendy; Gold, Daniel A.; Rosowski, Emily E.; Sprokholt, Joris K.; Lim, Daniel; Farid Arenas, Ailan; Melo, Mariane B.; Spooner, Eric; Yaffe, Michael B.; Saeij, Jeroen P. J.

2012-01-01

The obligate intracellular parasite Toxoplasma gondii secretes effector proteins into the host cell that manipulate the immune response allowing it to establish a chronic infection. Crosses between the types I, II and III strains, which are prevalent in North America and Europe, have identified several secreted effectors that determine strain differences in mouse virulence. The polymorphic rhoptry protein kinase ROP18 was recently shown to determine the difference in virulence between type I and III strains by phosphorylating and inactivating the interferon-γ (IFNγ)-induced immunity-related GTPases (IRGs) that promote killing by disrupting the parasitophorous vacuole membrane (PVM) in murine cells. The polymorphic pseudokinase ROP5 determines strain differences in virulence through an unknown mechanism. Here we report that ROP18 can only inhibit accumulation of the IRGs on the PVM of strains that also express virulent ROP5 alleles. In contrast, specific ROP5 alleles can reduce IRG coating even in the absence of ROP18 expression and can directly interact with one or more IRGs. We further show that the allelic combination of ROP18 and ROP5 also determines IRG evasion and virulence of strains belonging to other lineages besides types I, II and III. However, neither ROP18 nor ROP5 markedly affect survival in IFNγ-activated human cells, which lack the multitude of IRGs present in murine cells. These findings suggest that ROP18 and ROP5 have specifically evolved to block the IRGs and are unlikely to have effects in species that do not have the IRG system, such as humans. PMID:22761577

Quantifying the Risk of Human Toxoplasma gondii Infection Due to Consumption of Domestically Produced Lamb in the United States.

Science.gov (United States)

Guo, Miao; Mishra, Abhinav; Buchanan, Robert L; Dubey, Jitender P; Hill, Dolores E; Gamble, H Ray; Pradhan, Abani K

2016-07-01

Toxoplasma gondii is a prevalent protozoan parasite worldwide. Human toxoplasmosis is responsible for considerable morbidity and mortality in the United States, and meat products have been identified as an important source of T. gondii infections in humans. The goal of this study was to develop a farm-to-table quantitative microbial risk assessment model to predict the public health burden in the United States associated with consumption of U.S. domestically produced lamb. T. gondii prevalence in market lambs was pooled from the 2011 National Animal Health Monitoring System survey, and the concentration of the infectious life stage (bradyzoites) was calculated in the developed model. A log-linear regression and an exponential doseresponse model were used to model the reduction of T. gondii during home cooking and to predict the probability of infection, respectively. The mean probability of infection per serving of lamb was estimated to be 1.5 cases per 100,000 servings, corresponding to ∼6,300 new infections per year in the U.S. Based on the sensitivity analysis, we identified cooking as the most effective method to influence human health risk. This study provided a quantitative microbial risk assessment framework for T. gondii infection through consumption of lamb and quantified the infection risk and public health burden associated with lamb consumption.

Conjugated Linoleic Acid Stimulates Apoptosis in RH and Tehran Strains of Toxoplasma gondii, in Vitro.

Directory of Open Access Journals (Sweden)

Jebreil Shamseddin

2015-06-01

Full Text Available The aim of this study was to evaluate the effects of conjugated linoleic acid (CLA on apoptosis of tachyzoites of T. gondii, RH strain (type I and the cyst-forming Tehran strain (type II in vitro.Toxoplasma strains were injected into the peritoneal cavity of BALB/c mice. The Tehran strain forms cysts in the brain of mice. Bradyzoites within the cysts are reactivated to proliferative tachyzoites, by dexamethasone. Tachyzoites were aspirated from the peritoneum of infected mice, and the percentage of viable parasites was estimated with trypan blue staining. Tachyzoites were inoculated into HeLa cells cultivated in DMEM medium. Different concentrations of CLA were evaluated on T. gondii in HeLa cells by the tetrazolium (MTT colorimetric assay. Differentiation between apoptosis and cell death was determined by flow cytometry using Annexin V and propidium iodide (PI double staining. The statistical analysis performed by GraphPad Prism version 6.00.CLA induces apoptosis in virulent (RH and avirulent (Tehran strains of T. gondii. The results of MTT indicated that CLA could decrease the proliferation of tachyzoites of both strains in HeLa cells.Conjugated linoleic acid has anti-toxoplasmacidal activity on tachyzoites of T. gondii. Therefore, we recommended further studies on this component in order to achieve a new drug against the parasite.

Self-mating in the definitive host potentiates clonal outbreaks of the apicomplexan parasites Sarcocystis neurona and Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Jered M Wendte

2010-12-01

Full Text Available Tissue-encysting coccidia, including Toxoplasma gondii and Sarcocystis neurona, are heterogamous parasites with sexual and asexual life stages in definitive and intermediate hosts, respectively. During its sexual life stage, T. gondii reproduces either by genetic out-crossing or via clonal amplification of a single strain through self-mating. Out-crossing has been experimentally verified as a potent mechanism capable of producing offspring possessing a range of adaptive and virulence potentials. In contrast, selfing and other life history traits, such as asexual expansion of tissue-cysts by oral transmission among intermediate hosts, have been proposed to explain the genetic basis for the clonal population structure of T. gondii. In this study, we investigated the contributing roles self-mating and sexual recombination play in nature to maintain clonal population structures and produce or expand parasite clones capable of causing disease epidemics for two tissue encysting parasites. We applied high-resolution genotyping against strains isolated from a T. gondii waterborne outbreak that caused symptomatic disease in 155 immune-competent people in Brazil and a S. neurona outbreak that resulted in a mass mortality event in Southern sea otters. In both cases, a single, genetically distinct clone was found infecting outbreak-exposed individuals. Furthermore, the T. gondii outbreak clone was one of several apparently recombinant progeny recovered from the local environment. Since oocysts or sporocysts were the infectious form implicated in each outbreak, the expansion of the epidemic clone can be explained by self-mating. The results also show that out-crossing preceded selfing to produce the virulent T. gondii clone. For the tissue encysting coccidia, self-mating exists as a key adaptation potentiating the epidemic expansion and transmission of newly emerged parasite clones that can profoundly shape parasite population genetic structures or cause

Self-mating in the definitive host potentiates clonal outbreaks of the apicomplexan parasites Sarcocystis neurona and Toxoplasma gondii.

Science.gov (United States)

Wendte, Jered M; Miller, Melissa A; Lambourn, Dyanna M; Magargal, Spencer L; Jessup, David A; Grigg, Michael E

2010-12-23

Tissue-encysting coccidia, including Toxoplasma gondii and Sarcocystis neurona, are heterogamous parasites with sexual and asexual life stages in definitive and intermediate hosts, respectively. During its sexual life stage, T. gondii reproduces either by genetic out-crossing or via clonal amplification of a single strain through self-mating. Out-crossing has been experimentally verified as a potent mechanism capable of producing offspring possessing a range of adaptive and virulence potentials. In contrast, selfing and other life history traits, such as asexual expansion of tissue-cysts by oral transmission among intermediate hosts, have been proposed to explain the genetic basis for the clonal population structure of T. gondii. In this study, we investigated the contributing roles self-mating and sexual recombination play in nature to maintain clonal population structures and produce or expand parasite clones capable of causing disease epidemics for two tissue encysting parasites. We applied high-resolution genotyping against strains isolated from a T. gondii waterborne outbreak that caused symptomatic disease in 155 immune-competent people in Brazil and a S. neurona outbreak that resulted in a mass mortality event in Southern sea otters. In both cases, a single, genetically distinct clone was found infecting outbreak-exposed individuals. Furthermore, the T. gondii outbreak clone was one of several apparently recombinant progeny recovered from the local environment. Since oocysts or sporocysts were the infectious form implicated in each outbreak, the expansion of the epidemic clone can be explained by self-mating. The results also show that out-crossing preceded selfing to produce the virulent T. gondii clone. For the tissue encysting coccidia, self-mating exists as a key adaptation potentiating the epidemic expansion and transmission of newly emerged parasite clones that can profoundly shape parasite population genetic structures or cause devastating disease

Phenotypic and genotypic characterization of two Toxoplasma gondii isolates in free-range chickens from Uberlândia, Brazil.

Science.gov (United States)

Lopes, C S; Franco, P S; Silva, N M; Silva, D A O; Ferro, E A V; Pena, H F J; Soares, R M; Gennari, S M; Mineo, J R

2016-07-01

The aim of this study was to determine the seroprevalence of Toxoplasma gondii infection in free-range chickens from Uberlândia, Minas Gerais state, Brazil, and characterize the genotypic and phenotypic features of two isolates of this parasite, considering the importance of these hosts in the epidemiology of toxoplasmosis. Serum samples from 108 free-range chickens were obtained from ten different districts, and submitted to the modified agglutination test (MAT) for the presence of anti-T. gondii antibodies, and brain and heart tissue samples from infected chickens were processed for mouse bioassay. An overall seroprevalence of 71·3% was found and antibody titres ranged from 16 to 4096. After confirmation of seropositivity by mouse bioassay, the determination of the T. gondii genotypes of two isolates was performed by PCR-RFLP, using primers for the following markers: SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, new SAG2, Apico and CS3. These T. gondii isolates, designated TgChBrUD1and TgChBrUD2, were obtained from heart samples of free-range chickens. The TgChBrUD1 isolate belonged to ToxoDB PCR-RFLP genotype 11 and the TgChBrUD2 isolate belonged to ToxoDB PCR-RFLP genotype 6. Both isolates demonstrated high virulence in a rodent model, with the TgChBrUD1 isolate able to induce brain cysts, in accord with its pattern of multiplication rates in human fibroblast culture. Taken together, these results reveal high prevalence of T. gondii infection in free-range chickens throughout Uberlândia, indicating an important degree of oocyst environmental contamination and the existence of considerable risk for T. gondii transmission to humans by consumption of free-range chicken as a food source.

Chicken line-dependent mortality after experimental infection with three type IIxIII recombinant Toxoplasma gondii clones.

Science.gov (United States)

Schares, G; Herrmann, D C; Maksimov, P; Matzkeit, B; Conraths, F J; Moré, G; Preisinger, R; Weigend, S

2017-09-01

Three genetically different clones of Toxoplasma gondii, also different in mouse virulence, were studied by experimental infection in chickens. For the experiments, four chicken lines were used, which differed in phylogenetic origin and performance level: two white egg layer lines, one with high laying performance (WLA), one with low (R11) and two brown layer lines, also displaying high (BLA) and low (L68) egg number. Chickens were intraperitoneally infected with three different T. gondii isolates representing type IIxIII recombinant clones, i.e. showing both, type II- and type III-specific alleles. These clones (K119/2 2C10, B136/1 B6H6, K119/2 A7) had exhibited virulence differences in a mouse model. In chickens, a significantly higher mortality was observed in white layer lines, but not in brown layer lines, suggesting that differences in the phylogenetic background may influence the susceptibility of chickens for toxoplasmosis. In addition, antibody (IgY) levels varied in surviving chickens at 31 days post infection. While low to intermediate antibody levels were observed in white layers, intermediate to high levels were measured in brown layers. Infection with a T. gondii clone showing low chicken virulence resulted in higher antibody levels in all chicken lines compared to infection with T. gondii clones of intermediate or high chicken virulence. This was in agreement with the parasite load as determined by real-time PCR. Overall, results show that progeny resulting from natural sexual recombination of T. gondii clonal lineages, may differ in their virulence for mice and chickens. Copyright © 2016 Elsevier Inc. All rights reserved.

Using molecular epidemiology to track Toxoplasma gondii from terrestrial carnivores to marine hosts: implications for public health and conservation.

Science.gov (United States)

VanWormer, Elizabeth; Miller, Melissa A; Conrad, Patricia A; Grigg, Michael E; Rejmanek, Daniel; Carpenter, Tim E; Mazet, Jonna A K

2014-01-01

Environmental transmission of the zoonotic parasite Toxoplasma gondii, which is shed only by felids, poses risks to human and animal health in temperate and tropical ecosystems. Atypical T. gondii genotypes have been linked to severe disease in people and the threatened population of California sea otters. To investigate land-to-sea parasite transmission, we screened 373 carnivores (feral domestic cats, mountain lions, bobcats, foxes, and coyotes) for T. gondii infection and examined the distribution of genotypes in 85 infected animals sampled near the sea otter range. Nested PCR-RFLP analyses and direct DNA sequencing at six independent polymorphic genetic loci (B1, SAG1, SAG3, GRA6, L358, and Apico) were used to characterize T. gondii strains in infected animals. Strains consistent with Type X, a novel genotype previously identified in over 70% of infected sea otters and four terrestrial wild carnivores along the California coast, were detected in all sampled species, including domestic cats. However, odds of Type X infection were 14 times higher (95% CI: 1.3-148.6) for wild felids than feral domestic cats. Type X infection was also linked to undeveloped lands (OR = 22, 95% CI: 2.3-250.7). A spatial cluster of terrestrial Type II infection (P = 0.04) was identified in developed lands bordering an area of increased risk for sea otter Type II infection. Two spatial clusters of animals infected with strains consistent with Type X (P ≤ 0.01) were detected in less developed landscapes. Differences in T. gondii genotype prevalence among domestic and wild felids, as well as the spatial distribution of genotypes, suggest co-existing domestic and wild T. gondii transmission cycles that likely overlap at the interface of developed and undeveloped lands. Anthropogenic development driving contact between these cycles may increase atypical T. gondii genotypes in domestic cats and facilitate transmission of potentially more pathogenic genotypes to humans, domestic animals

Using molecular epidemiology to track Toxoplasma gondii from terrestrial carnivores to marine hosts: implications for public health and conservation.

Directory of Open Access Journals (Sweden)

Elizabeth VanWormer

Full Text Available Environmental transmission of the zoonotic parasite Toxoplasma gondii, which is shed only by felids, poses risks to human and animal health in temperate and tropical ecosystems. Atypical T. gondii genotypes have been linked to severe disease in people and the threatened population of California sea otters. To investigate land-to-sea parasite transmission, we screened 373 carnivores (feral domestic cats, mountain lions, bobcats, foxes, and coyotes for T. gondii infection and examined the distribution of genotypes in 85 infected animals sampled near the sea otter range.Nested PCR-RFLP analyses and direct DNA sequencing at six independent polymorphic genetic loci (B1, SAG1, SAG3, GRA6, L358, and Apico were used to characterize T. gondii strains in infected animals. Strains consistent with Type X, a novel genotype previously identified in over 70% of infected sea otters and four terrestrial wild carnivores along the California coast, were detected in all sampled species, including domestic cats. However, odds of Type X infection were 14 times higher (95% CI: 1.3-148.6 for wild felids than feral domestic cats. Type X infection was also linked to undeveloped lands (OR = 22, 95% CI: 2.3-250.7. A spatial cluster of terrestrial Type II infection (P = 0.04 was identified in developed lands bordering an area of increased risk for sea otter Type II infection. Two spatial clusters of animals infected with strains consistent with Type X (P ≤ 0.01 were detected in less developed landscapes.Differences in T. gondii genotype prevalence among domestic and wild felids, as well as the spatial distribution of genotypes, suggest co-existing domestic and wild T. gondii transmission cycles that likely overlap at the interface of developed and undeveloped lands. Anthropogenic development driving contact between these cycles may increase atypical T. gondii genotypes in domestic cats and facilitate transmission of potentially more pathogenic genotypes to humans

Prevalence and genetic characterization of Toxoplasma gondii in free-range chickens from grocery stores and farms in Maryland, Ohio and Massachusetts, USA.

Science.gov (United States)

Ying, Yuqing; Verma, Shiv K; Kwok, Oliver C H; Alibana, Fatima; Mcleod, Rima; Su, Chunlei; Dubey, Jitender P; Pradhan, Abani K

2017-05-01

Chickens are considered important in the epidemiology of Toxoplasma gondii. Chicken hearts (n = 1185) obtained from grocery stores were tested for T. gondii infection. Antibodies to T. gondii were assayed in fluid removed from the heart cavity using the modified agglutination test (MAT) at 1:5, 1:25, and 1:100 dilutions. MAT antibodies were detected in 222 hearts at 1:5 dilution and 8 hearts at 1:25 dilution, but none were positive at 1:100 dilution. Seropositive (n = 230, 19.4%) chicken hearts were bioassayed in mice and seronegative (n = 157) chickens were bioassayed in cats. Viable T. gondii was not isolated from any hearts by bioassays in mice. The 2 cats fed 60 and 97 hearts did not excrete T. gondii oocysts. The results indicate a low prevalence of viable T. gondii in chickens from grocery stores. Molecular typing of 23 archived T. gondii strains isolated from free-range chickens from Ohio and Massachusetts using the 10 PCR-RFLP markers including SAG1, SAG2 (5'-3'SAG2 and altSAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico revealed that seven were ToxoDB PCR-RFLP genotype #1, 11 were genotype #2, one was genotype #3, three were genotype #170, and one was mixed genotype. These results indicate that the clonal genotypes #1 (type II), #2 (type III), and #3 (type II variant) are common in free-range chickens.

Infection with Toxoplasma gondii in a red kangaroo (Macropus rufus and a Patagonian mara (Dolichotis patagonum in captivity

Directory of Open Access Journals (Sweden)

Nataly Díaz-Ayala

Full Text Available Abstract Toxoplasmosis is an infectious, zoonotic and parasitic disease, caused by Toxoplasma gondii. In this manucript, two cases of infection with T. gondii in captive animals from a zoological park in the central region of Chile are described. One case was a red kangaroo (Macropus rufus, which is highly susceptible to the infection, and the other was a Patagonian mara (Dolichotis patagonum, a rodent in which there is no previous report of the infection. Both animals had myocarditis, with the presence of intralesional tachizoites and cysts suggestive of infection with T. gondii. This infection was confirmed by immunohistochemistry in both animals. The origin of the infection is unknown, but it is likely that free ranging domestic felines were associated with the dissemination of the parasites. This highlights the importance of controlling the domestic animal populations in zoological parks. To the best of our knowledge, this is the first time that T. gondii infection is described in a Patagonian mara, adding a new host for this infectious agent.

Clinical Toxoplasma gondii, Hammondia heydorni, and Sarcocystis spp. infections in dogs.

Science.gov (United States)

Dubey, J P; Ross, A D; Fritz, D

2003-12-01

Concurrent infections with coccidians Toxoplasma gondii, Sarcocystis spp., and a Hammondia heydorni-like parasite were identified in tissues of three littermate pups on a Kelpie dog breeding farm in Australia. In total, 20 pups in four litters had died following vaccination with an attenuated distemper virus vaccine. Toxoplasma gondii tachyzoites were identified immunohistochemically in tissues of two dogs. Sarcocystis sp. sporocysts were seen in the intestinal lamina propria of two dogs. Asexual and sexual stages of H. heydorni-like parasite were found in enterocytes of the small intestine of two dogs. Ultrastructural development of schizonts and gamonts of this parasite is described. None of the protozoa in these dogs reacted with antibodies to Neospora caninum. Feeding of uncooked tissue of sheep was considered to be the likely source of infection for these coccidians in dogs.

Occurrence of Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic forest, State of Sao Paulo, Brazil

Science.gov (United States)

Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small mammals and rodents play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 4...

Seroprevalence of Toxoplasma gondii in wild marsupials and rodents from the Atlantic forest of Pernambuco State, Northeastern region, Brazil

Science.gov (United States)

Felids are important in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts in their feces. Cats are considered to acquire T. gondii infection in nature by ingesting tissues of small mammals and birds. Serum samples of feral 22...

Antibodies to Toxoplasma gondii and Leishmania spp. in domestic cats from Luanda, Angola.

Science.gov (United States)

Lopes, Ana Patrícia; Oliveira, Ana Cristina; Granada, Sara; Rodrigues, Filipa T; Papadopoulos, Elias; Schallig, Henk; Dubey, Jitender P; Cardoso, Luís

2017-05-30

Toxoplasma gondii and Leishmania spp. are zoonotic protozoa of importance to animal and public health. The present study aimed to assess for the first time the seroprevalence of these zoonotic parasites in a domestic feline population living in Luanda, Angola. One hundred and two cats were sampled at a veterinary medical centre, from May 2014 to February 2016. The age of the cats ranged from 2.5 to 143 months (median: 12 months; interquartile range: 7.5-24). Serum samples were tested for immunoglobulin (Ig) G antibodies to T. gondii at two-fold dilutions of 1:20 to 1:2560 with a modified agglutination test (MAT) commercial kit. The direct agglutination test (DAT) for titration of IgG antibodies specific to Leishmania spp. used a standard freeze-dried antigen at a concentration of 5×10 7 promastigotes per milliliter, following a predefined protocol. Two-fold dilution series ranging from 1:25 to 1:800 were tested, with a cut-off titre of 100 chosen for seropositivity. Four out of 102 cats (3.9%; 95% confidence interval [CI]: 1.1-9.7) had antibodies to T. gondii: one had a titer of 20, one a titer of 160, and two had a titer≥2560. No cat (0.0%; CI: 0.0-3.5) was found seropositive for Leishmania spp. A statistically significant difference was found between T. gondii seroprevalence and Leishmania spp. seroprevalence (p=0.043). The odds of a cat being seropositive to T. gondii increased by an average factor of 1.58 for each 1-year increase in age (p=0.003). The sampled cats were well-cared animals and may not represent the overall feline population of Angola at the national and city levels. The fact that only 12 out of the 102 sampled cats ate or had access to raw or undercooked meat and/or viscera may have reduced the likelihood of finding seropositive results. Under these circumstances, additional studies, including a larger number of cats, are necessary for a more comprehensive assessment of the zoonotic risk posed by these animals in Angola. Copyright © 2017

Increased Toxoplasma gondii positivity relative to age in 125 Scottish sheep flocks; evidence of frequent acquired infection

Science.gov (United States)

2011-01-01

Toxoplasma gondii seroprevalence was determined in 3333 sheep sera from 125 distinct sheep flocks in Scotland, with the majority of flocks being represented by 27 samples, which were collected between July 2006 and August 2008. The selected farms give a representative sample of 14 400 sheep holdings identified in the Scottish Government census data from 2004. Overall T. gondii seroprevalence, at individual sheep level, was determined to be 56.6%; each flock tested, had at least a single positive animal and in four flocks all ewes tested positive. The seroprevalence of sheep increased from 37.7% in one year old stock to 73.8% in ewes that were older than six years, showing that acquired infections during the life of the animals is frequent and that environmental contamination by T. gondii oocysts must be significant. The median within-flock seroprevalence varied significantly across Scotland, with the lowest seroprevalence of 42.3% in the South and the highest seroprevalence of 69.2% in the far North of Scotland and the Scottish Islands, while the central part of Scotland had a seroprevalence of 57.7%. This distribution disequilibrium may be due to the spread and survival of oocysts on pasture and lambing areas. A questionnaire accompanying sampling of flocks identified farms that used Toxovax®, a commercial vaccine that protects sheep from abortion due to T. gondii infection. Only 24.7% of farmers used the vaccine and the vaccine did not significantly affect the within flock seroprevalence for T. gondii. The implications for food safety and human infection are discussed. PMID:22189159

Molecular detection of Toxoplasma gondii and Neospora caninum in birds from South Africa.

Science.gov (United States)

Lukášová, Radka; Kobédová, Kateřina; Halajian, Ali; Bártová, Eva; Murat, Jean-Benjamin; Rampedi, Kgethedi Michael; Luus-Powell, Wilmien J

2018-02-01

There are not any records on the detection of Toxoplasma gondii and Neospora caninum in tissues of wild birds in the African continent. The aim of the study was to investigate the occurrence of DNA from these protozoan parasites in brain tissue samples collected in years 2014-2015 from 110 wild and domestic birds of 15 orders. Birds came mainly from the province of Limpopo (n=103); the other seven birds came from other five provinces of South Africa. Parasite DNAs were detected by PCR in animal brains. While all samples were negative for N. caninum, T. gondii DNA was detected in three (2.7%) birds: a Red-eyed Dove (Streptopelia semitorquata), a Laughing Dove (S. senegalensis) and a Southern-Yellow-billed Hornbill (Tockus leucomelas), all from Limpopo province. Positive samples were selected for genotyping by a 15 microsatellite markers method in a single multiplex PCR assay. Only the sample from the Red-eyed Dove was successfully genotyped and characterized as type II. This is the first detection of T. gondii in tissue of native African wild birds and the first study focusing on N. caninum in birds from South Africa. Copyright © 2017. Published by Elsevier B.V.

Eficiencia de cultivo in vitro de Toxoplasma gondii en las líneas celulares THP1 y Vero

Directory of Open Access Journals (Sweden)

Jorge Andrés Cuellar

2012-03-01

Full Text Available Introducción. El cultivo in vitro es un método importante para la obtención de Toxoplasma gondii confines de diagnóstico clínico o biotecnológico. Objetivo. Determinar el porcentaje de invasión y producción de T. gondii en las líneas celulares THP1y Vero. Materiales y métodos. Se determinó la curva de crecimiento para las células Vero y THP1 por conteoen hemocitómetro. Posteriormente, se identificó el porcentaje de invasión de T. gondii en células THP1y Vero por citometría de flujo, en diferentes proporciones célula/taquizoíto de 1/5, 1/20, 1/50. Por otrolado, se calculó el índice de rendimiento de T. gondii, cepa RH, y del aislamiento CIBM1 en célulasTHP1. Resultados. Las células Vero crecen más rápidamente que las células THP1, con un crecimientoexponencial en un periodo de siete días. El aislamiento CIBM1 infecta las células THP1 en las tresproporciones diferentes de 1/5,1/20 y 1/50 con porcentajes de invasión de 57,1 %, 15,5 % y 12,2 %, yen células Vero, de 25,3 %, 17,8 % y 8,8 %. La cepa RH de T. gondii mostró porcentajes de invasiónmás bajos, de 32,6 %, 14,8 % y 8,1 % en células THP1 y de 22,3 %, 14,1 % y 3,4 % en células Vero. Conclusiones. El aislamiento CIBM1 presentó mayor rendimiento con respecto a la cepa RH de T.gondii en células THP1, siendo estas células una buena línea para estudiar el proceso de invasión yprobar candidatos farmacológicos para reducir la infección por T. gondii.   doi: http://dx.doi.org/10.7705/biomedica.v32i3.485

Seroprevalence of Toxoplasma gondii infection in domestic pigs reared under different management systems in Zimbabwe

Directory of Open Access Journals (Sweden)

T. Hove

2005-09-01

Full Text Available Serum samples from 474 domestic pigs (Sus scrofa from Zimbabwe were tested for anti-Toxoplasma gondii IgG antibodies using the indirect fluorescent antibody test. The results showed that T. gondii infection is widespread in Zimbabwean pigs. Seroprevalence was lowest in fattening pigs from large and small-scale commercial farms that practise good hygiene (19.75 % of 238 and highest in backyard scavenging pigs (35.71 % of 70. Only 11.7 % (11 of the 127 positive samples had titres of > 1:400 and nine (81.82 % of these 11 originated from pigs reared under poor hygienic conditions. A prevalence of 3.51 % was found in the same group of fattening pigs using an indirect IgG enzyme-linked immunosorbent assay at the single serum dilution of 1:400. The serosurvey shows the importance of modern intensive husbandry systems in reducing the prevalences of T. gondii infection in domestic pigs.

Malaria parasite cGMP-dependent protein kinase regulates blood stage merozoite secretory organelle discharge and egress.

Directory of Open Access Journals (Sweden)

Christine R Collins

2013-05-01

Full Text Available The malaria parasite replicates within an intraerythrocytic parasitophorous vacuole (PV. Eventually, in a tightly regulated process called egress, proteins of the PV and intracellular merozoite surface are modified by an essential parasite serine protease called PfSUB1, whilst the enclosing PV and erythrocyte membranes rupture, releasing merozoites to invade fresh erythrocytes. Inhibition of the Plasmodium falciparum cGMP-dependent protein kinase (PfPKG prevents egress, but the underlying mechanism is unknown. Here we show that PfPKG activity is required for PfSUB1 discharge into the PV, as well as for release of distinct merozoite organelles called micronemes. Stimulation of PfPKG by inhibiting parasite phosphodiesterase activity induces premature PfSUB1 discharge and egress of developmentally immature, non-invasive parasites. Our findings identify the signalling pathway that regulates PfSUB1 function and egress, and raise the possibility of targeting PfPKG or parasite phosphodiesterases in therapeutic approaches to dysregulate critical protease-mediated steps in the parasite life cycle.

Spatial epidemiology of Toxoplasma gondii infection in goats in Serbia

Directory of Open Access Journals (Sweden)

Vitomir Djokić

2014-05-01

Full Text Available A major risk factor for Toxoplasma gondii infection is consumption of undercooked meat. Increasing demand for goat meat is likely to promote the role of this animal for human toxoplasmosis. As there are virtually no data on toxoplasmosis in goats in Serbia, we undertook a cross-sectional serological study, including prediction modelling using geographical information systems (GIS. Sera from 431 goats reared in 143 households/farms throughout Serbia, sampled between January 2010 and September 2011, were examined for T. gondii antibodies by a modified agglutination test. Seroprevalence was 73.3% at the individual level and 84.6% at the farm level. Risk factor analysis showed above two-fold higher risk of infection for goats used for all purposes compared to dairy goats (P = 0.012, almost seven-fold higher risk for goats kept as sole species versus those kept with other animals (P = 0.001 and a two-fold lower risk for goats introduced from outside the farm compared to those raised on the farm (P = 0.027. Moreover, households/farms located in centre-eastern Serbia were found to be less often infected than those in northern Serbia (P = 0.004. The risk factor analysis was fully supported by spatial analysis based on a GIS database containing data on origin, serology, land cover, elevation, meteorology and a spatial prediction map based on kriging analysis, which showed western Serbia as the area most likely for finding goats positive for T. gondii and centre-eastern Serbia as the least likely. In addition, rainfall favoured seropositivity, whereas temperature, humidity and elevation did not.

SPORULATION AND SURVIVAL OF TOXOPLASMA GONDII OOCYSTS IN SEA WATER

Science.gov (United States)

Since 1992, we have been collaborating in studies on southern sea otters (Enhdyra lutris nereis) as part of a program to define factors which may be responsible for limiting the growth of the southern sea otter population. We previously demonstrated Toxoplasma gondii in sea otter...

Occurrence of infection with Toxoplasma gondii and factors associated with transmission in broiler chickens and laying hens in different raising systems

Directory of Open Access Journals (Sweden)

Patricia R. Millar

2012-03-01

Full Text Available Toxoplasmosis is a zoonotic disease caused by the protozoan Toxoplasma gondii. The aim of the present study was to determine the occurrence and identify the risk factors associated with transmission of T. gondii to chickens raised in different systems (free-ranged and confined to produce eggs or meat. The 810 animals were allocated in two experimental groups according to the production system purpose: 460 broiler chickens (Group 1 and 350 layer chickens (Group 2. In order to analyze the possible factors involved in T. gondii infection in the chickens, an epidemiological questionnaire was developed for all properties.The serological detection of anti-Toxoplasma gondii antibodies was performed by Indirect Immunofluorescence (IFAT and by Enzime Linked Imunossorbent Assay (ELISA. Since the agreement index (kappa between these two serological techniques was considered high, 21.2% of the 810 animals were considered reactive. In Group 1, 12.2% (56/460 were positive, while in the Group 2 the positivity rate was 33.1% (116/350. The production system may be influencing the seropositivity of the animals in both groups. However, only in Group 2 it was possible to notice a statistically significant relationship between the breeding system and the frequency of positive sera. This result indicates that, at least for laying hens, the production system is directly involved in T. gondii infection. The contact with cats in Group 1 did not influence the distribution of seroreactive animals, but in Group 2 a significant relationship was observed. The occurrence of anti-T. gondii antibodies was high in both groups (broiler and posture chickens. Free-ranged chickens raised for egg production proved to be the most exposed group to the T. gondii infection. This can be related to the fact that these animals stay for longer periods in the farms, in direct contact with possibly contaminated soil by the presence of domestic cats.

Genetic characterization of Toxoplasma gondii isolates from Portugal, Austria, and Israel reveals higher genetic variability within the type II lineage

Science.gov (United States)

This study compared genetic diversity of Toxoplasma gondii isolates from Portugal, Austria and Israel. For this, we genotyped 90 T. gondii isolates (16 from Portugal, 67 from Austria and 7 from Israel) using 10 nested PCR-restriction length polymorphism (RFLP) genetic markers and 15 microsatellite (...

An updated literature review on maternal-fetal and reproductive disorders of Toxoplasma gondii infection.

Science.gov (United States)

Fallahi, S; Rostami, A; Nourollahpour Shiadeh, M; Behniafar, H; Paktinat, S

2018-03-01

Toxoplasma gondii infection is one of the most prevalent infectious disease with worldwide distribution. Congenital toxoplasmosis is annually responsible for 1.20 million disability-adjusted life years around the world, but often it is overlooked many countries. We performed an updated review to summarize the current researches on fetal, neonatal and maternal consequences of T. gondii infection and also adverse effects of toxoplasmosis on women reproductive organs. T. gondii infection could be cause of several abnormalities from hydrocephalus, microcephaly, deafness, abortion and still birth in fetal to psychomotor retardation, intellectual disability, hearing loss, slower postnatal motor development during the first year of life; and chorioretinitis, cryptogenic epilepsy and autism spectrum disorders in newborns. Moreover, this infection is related with neuropsychiatric disorders such as anxiety, schizophrenia spectrum disorders, depression, decreased weight, autoimmune thyroid diseases, self-directed violence, violent suicide attempts in mothers. This literature review emphasized that toxoplasmosis could be an important neglected factor endometritis, ovarian dysfunction, impaired folliculogenesis, ovarian and uterine atrophy, decrease in reproductive organs weight and reproductive performance in women. We reviewed role of the immunological profile such as pro-infiammatory cytokines and hormonal changes as main potential mechanisms related to this infection and development of maternal-fetal and reproductive disorders. T. gondii is associated with several brain related disorders in both mothers and newborns, and also it is cause of several abnormalities in reproductive organs. Early diagnosis and treatment of the infection could be effective to significantly improve the clinical outcome. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Seroepidemiologic study on the prevalence of Toxoplasma gondii and Trichinella spp. infections in black bears (Ursus americanus) in Pennsylvania, USA.

Science.gov (United States)

Dubey, Jitender P; Brown, Justin; Ternent, Mark; Verma, Shiv K; Hill, Dolores E; Cerqueira-Cézar, Camila K; Kwok, Oliver C H; Calero-Bernal, Rafael; Humphreys, Jan G

2016-10-15

The protozoan Toxoplasma gondii and the metazoan Trichinella spp. infect virtually all warm-blooded animals, including birds, humans, livestock, and marine mammals. Both parasitic infections can cause serious illness in human beings and can be acquired by ingesting under-cooked meat harboring infective stages. Approximately 3500 black bears (Ursus americanus) are legally-harvested each year in Pennsylvania, USA during the November hunting season. Among animals found infected with T. gondii, the prevalence of T. gondii is the highest among black bears in the USA; however, little is currently known of epidemiology of toxoplasmosis in this host species. Serum samples were collected during the winters of 2015 and 2016 from adult female bears and their nursing cubs or yearlings while they were still in their dens. Additionally, archived sera from bear samples collected throughout the year, including hunter-harvested bears in November and trapped bears in the summer, were serologically tested. Antibodies to T. gondii were assayed by the modified agglutination test (MAT, cut-off 1:25) and antibodies to Trichinella spp. were assayed using a commercial enzyme-linked immunosorbent assay (ELISA). Overall, T. gondii antibodies were found in 87.6% (206/235) of adults, and 44.1% (30/68) of yearlings. In March 2015/2016 sampling, antibodies to T. gondii were found in 94% (30/32) adult female bears while in their den. Antibodies were detected in 5% (3/66) of the nursing cubs in the dens of these sows. One positive cub had a MAT titer of 1:160 and two were positive at the 1:25 dilution but not at 1:50. The adult females of these cubs had MAT titers ranging from 1:400 to 1:3200. Antibodies to Trichinella spp. were found in 3% (6/181) of adults and 3.6% (1/28) of yearlings; these 7 bears were also seropositive for T. gondii. No antibodies to Trichinella spp. were detected in the sera of 44 nursing cubs tested. The finding of T. gondii antibodies in only 3 of 66 cubs, and higher

Characterisation of Toxoplasma gondii isolates using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) of the non-coding Toxoplasma gondii (TGR)-gene sequences

DEFF Research Database (Denmark)

Høgdall, Estrid; Vuust, Jens; Lind, Peter

2000-01-01

of using TGR gene variants as markers to distinguish among T. gondii isolates from different animals and different geographical sources. Based on the band patterns obtained by restriction fragment length polymorphism (RFLP) analysis of the polymerase chain reaction (PCR) amplified TGR sequences, the T...

Seroprevalence of Toxoplasma gondii and Trichinella spiralis in North Carolina black bears (Ursus americanus).

Science.gov (United States)

Nutter, F B; Levine, J F; Stoskopf, M K; Gamble, H R; Dubey, J P

1998-10-01

Serum samples from 143 hunter-killed black bears were collected during the 1996 and 1997 black bear hunting seasons in eastern North Carolina. All samples were tested for antibodies to Toxoplasma gondii by the modified agglutination test. Antibodies to T. gondii were present in 120 of 143 (84%) bears. Females had significantly higher titers than males (Wilcoxon rank sums test, P = 0.045), and titers increased with age (Jonckheere test, P = 0.01). Samples collected during 1996 (n = 79) were tested for antibodies to Trichinella spiralis by enzyme-linked immunosorbent assay. No samples were positive for antibodies to T. spiralis.

Toxoplasma gondii infection reduces predator aversion in rats through epigenetic modulation in the host medial amygdala.

Science.gov (United States)

Hari Dass, Shantala Arundhati; Vyas, Ajai

2014-12-01

Male rats (Rattus novergicus) infected with protozoan Toxoplasma gondii relinquish their innate aversion to the cat odours. This behavioural change is postulated to increase transmission of the parasite to its definitive felid hosts. Here, we show that the Toxoplasma gondii infection institutes an epigenetic change in the DNA methylation of the arginine vasopressin promoter in the medial amygdala of male rats. Infected animals exhibit hypomethylation of arginine vasopressin promoter, leading to greater expression of this nonapeptide. The infection also results in the greater activation of the vasopressinergic neurons after exposure to the cat odour. Furthermore, we show that loss of fear in the infected animals can be rescued by the systemic hypermethylation and recapitulated by directed hypomethylation in the medial amygdala. These results demonstrate an epigenetic proximate mechanism underlying the extended phenotype in the Rattus novergicus-Toxoplasma gondii association. © 2014 John Wiley & Sons Ltd.

Seroepidemiology of infection with Toxoplasma gondii in migrant agricultural workers living in poverty in Durango, Mexico.

Science.gov (United States)

Alvarado-Esquivel, Cosme; Campillo-Ruiz, Federico; Liesenfeld, Oliver

2013-04-20

Migrant agricultural workers are a group of people living in poverty with poor housing, sanitary conditions and hygiene practices. Little is known about the epidemiology of infection with Toxoplasma gondii in migrant agricultural workers. We investigated the presence of anti-Toxoplasma IgG and IgM antibodies in 173 migrant workers hired for seasonal agricultural work in Durango State in northern Mexico using enzyme-linked immunoassays. Of the 173 migrant workers (mean age 34.82 ± 14.01 years), 50 (28.9%) had anti-Toxoplasma IgG antibodies and 36 (20.8%) had anti-Toxoplasma IgM antibodies. Seroprevalence was not influenced by gender, age, birth place, or educational level. In contrast, seroprevalence was significantly higher in workers residing in rural areas than those in urban or suburban areas. Migrant workers suffering from memory impairment, dizziness, or syncope had significantly higher seroprevalence of anti-T. gondii IgG antibodies than those without such clinical features. Logistic regression analysis showed that T. gondii exposure was positively associated with consumption of unwashed raw vegetables (OR = 2.39; 95% CI: 1.06-5.35; P = 0.03) and low frequency of eating out of home (OR = 3.87; 95% CI: 1.43-10.42; P = 0.007), and negatively associated with national trips (OR = 0.30; 95% CI: 0.13-0.65; P = 0.003) and consumption of raw milk (OR = 0.40; 95% CI: 0.18-0.87; P = 0.02). Other behavioral characteristics including consumption of meat or untreated water were not associated with T. gondii infection. This is the first report of T. gondii infection in internal migrant agricultural workers living in poverty. Results deserve further investigation of causal relations between clinical symptoms and infection, and may be useful for optimal planning of preventive measures.

Evidence of feline immunodeficiency virus, feline leukemia virus, and Toxoplasma gondii in feral cats on Mauna Kea, Hawaii.

Science.gov (United States)

Danner, Raymond M; Goltz, Daniel M; Hess, Steven C; Banko, Paul C

2007-04-01

We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats (Felis catus) on Mauna Kea Hawaii from April 2002 to May 2004. Six of 68 (8.8%) and 11 of 68 (16.2%) cats were antibody positive to FIV and antigen positive for FeLV, respectively; 25 of 67 (37.3%) cats were seropositive to T. gondii. Antibodies to FeLV and T. gondii occurred in all age and sex classes, but FIV occurred only in adult males. Evidence of current or previous infections with two of these infectious agents was detected in eight of 64 cats (12.5%). Despite exposure to these infectious agents, feral cats remain abundant throughout the Hawaiian Islands.

Seroprevalence of Toxoplasma gondii, Sarcocystis neurona, and Encephalitozoon cuniculi in three species of lemurs from St. Catherines Island, GA, USA.

Science.gov (United States)

Yabsley, Michael J; Jordan, Carly N; Mitchell, Sheila M; Norton, Terry M; Lindsay, David S

2007-03-15

In the current study, we determined the seroprevalence of Toxoplasma gondii, Sarcocystis neurona, and Encephalitozoon cuniculi in three species of lemurs from St. Catherines Island, Georgia. Serum samples were tested from 52 ring-tailed lemurs (Lemur catta), six blue-eyed black lemurs (Eulemur macaco flavifrons), and four black and white ruffed lemurs (Varecia variegata variegata) using an agglutination assay. Three ring-tailed lemurs (5.8%) were positive for T. gondii (titer of 1:50); one ring-tailed lemur (1.9%) and one black and white ruffed lemur (25%) were positive for S. neurona (titers of 1:1000); and one ring-tailed lemur (1.9%) was positive for E. cuniculi (titer of 1:400). All blue-eyed black lemurs were negative for antibodies to T. gondii, S. neurona, and E. cuniculi. This is the first detection of antibodies to T. gondii in ring-tailed lemurs and antibodies to S. neurona and E. cuniculi in any species of prosimian.

Risk factors for Toxoplasma gondii infection in Kohat District, Pakistan

Directory of Open Access Journals (Sweden)

Gul Naila

2017-01-01

Full Text Available Toxoplasma gondii is a widespread zoonotic parasite that is the causative agent for toxoplasmosis in human and completes its life cycle in separate hosts. Considering the significance of the infection, the current study was designed to asses to various risk factors for the parasite transmission to human in Kohat District, Pakistan. A total of 122 suspected individuals were asked to fill pre-designed questionnaire. A total of 44 (36.07% individuals were found to be infected with Toxoplasma gondii. Handling pets and birds, untreated water, unpasteurized milk and undercooked meat were found to be associated with infection. Raw vegetables and blood transfusion were not found to be associated with infection in our study. Thus, it can be concluded that Toxoplasma gondiiis is a prevalent zoonotic agent in Kohat, Pakistan and various prophylactic measures like hand washing, cooking meat properly, wearing gloves while contacting pets and birds, treating water and pasteurizing milk will be very helpful to reduce disease burden in the study area.

[i]Toxoplasma gondii[/i] in protected wildlife in the Tatra National Park (TANAP, Slovakia

Directory of Open Access Journals (Sweden)

Ludmila Turčeková

2014-06-01

Full Text Available [i]Toxoplasma gondii[/i] is an obligatory intracellular protozoan parasite that infects a broad spectrum of warm-blooded vertebrate species. As a part of the food chain, farm animals play a significant role in transmission of [i]T. gondii [/i]to humans, while rats and mice serve as a main source of infection for free-living animals. The spread of toxoplasmosis in the human population is due to the interchange of the domestic and sylvatic cycles. During 2009–2011, a survey on toxoplasmosis distribution was conducted in wildlife of the Tatra National Park (TANAP in Slovakia. A total of 60 animals were examined. The presence of [i]T. gondii[/i] was detected by means of molecular methods based on TGR1E gene analyses. The highest prevalence was recorded in birds (40.0%, followed by carnivores (30.8% and rodents (18.2%. RFLP analyses of SAG2 locus confirmed in birds the genotype II and III, belonging to the avirulent strain; rodents exclusively had genotype I, characterised as a virulent train, and in carnivores all three genotypes were detected. These results present the first survey on the parasite’s occurrence in several species of free-living animals in the TANAP area. An epidemiological study confirmed the prevalence of 30.0%, implicitly referring to the level of environmental contamination with [i]T. gondii [/i]oocysts.

Frequency of exposure of endangered Caspian seals to Canine distemper virus, Leptospira interrogans, and Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Somayeh Namroodi

Full Text Available Canine distemper virus (CDV, Leptospira interrogans, and Toxoplasma gondii are potentially lethal pathogens associated with decline in marine mammal populations. The Caspian Sea is home for the endangered Caspian seal (Pusa caspica. In the late 1990s and early 2000s, CDV caused a series of mortality events involving at least several thousand Caspian seals. To assess current infection status in Caspian seals, we surveyed for antibodies to three pathogens with potential to cause mortality in marine mammals. During 2015-2017, we tested serum samples from 36, apparently healthy, Caspian seals, accidentally caught in fishing nets in the Caspian Sea off Northern Iran, for antibodies to CDV, L. interrogans, and T. gondii, by virus neutralization, microscopic agglutination, and modified agglutination, respectively. Twelve (33%, 6 (17%, and 30 (83% samples were positive for CDV, L. interrogans and T. gondii antibodies, respectively. The highest titers of CDV, L. interrogans, and T. gondii antibodies were 16, 400, and 50, respectively. Frequencies of antibody to these pathogens were higher in seals >1 year old compared to seals <1 year old. Two serovars of L. interrogans (Pomona and Canicola were detected. Our results suggest a need for additional studies to clarify the impact of these pathogens on Caspian seal population decline and the improvement of management programs, including systematic screening to detect and protect the remaining population from disease outbreaks.

Frequency of exposure of endangered Caspian seals to Canine distemper virus, Leptospira interrogans, and Toxoplasma gondii.

Science.gov (United States)

Namroodi, Somayeh; Shirazi, Amir S; Khaleghi, Seyyed Reza; N Mills, James; Kheirabady, Vahid

2018-01-01

Canine distemper virus (CDV), Leptospira interrogans, and Toxoplasma gondii are potentially lethal pathogens associated with decline in marine mammal populations. The Caspian Sea is home for the endangered Caspian seal (Pusa caspica). In the late 1990s and early 2000s, CDV caused a series of mortality events involving at least several thousand Caspian seals. To assess current infection status in Caspian seals, we surveyed for antibodies to three pathogens with potential to cause mortality in marine mammals. During 2015-2017, we tested serum samples from 36, apparently healthy, Caspian seals, accidentally caught in fishing nets in the Caspian Sea off Northern Iran, for antibodies to CDV, L. interrogans, and T. gondii, by virus neutralization, microscopic agglutination, and modified agglutination, respectively. Twelve (33%), 6 (17%), and 30 (83%) samples were positive for CDV, L. interrogans and T. gondii antibodies, respectively. The highest titers of CDV, L. interrogans, and T. gondii antibodies were 16, 400, and 50, respectively. Frequencies of antibody to these pathogens were higher in seals >1 year old compared to seals <1 year old. Two serovars of L. interrogans (Pomona and Canicola) were detected. Our results suggest a need for additional studies to clarify the impact of these pathogens on Caspian seal population decline and the improvement of management programs, including systematic screening to detect and protect the remaining population from disease outbreaks.

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal.

Science.gov (United States)

Onuma, Selma Samiko Miyazaki; Melo, Andréia Lima Tomé; Kantek, Daniel Luis Zanella; Crawshaw-Junior, Peter Gransden; Morato, Ronaldo Gonçalves; May-Júnior, Joares Adenílson; Pacheco, Thábata dos Anjos; Aguiar, Daniel Moura de

2014-01-01

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.

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal

Directory of Open Access Journals (Sweden)

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.

Genetic characterization of Toxoplasma gondii from Brazilian wildlife revealed abundant new genotypes.

Science.gov (United States)

Vitaliano, S N; Soares, H S; Minervino, A H H; Santos, A L Q; Werther, K; Marvulo, M F V; Siqueira, D B; Pena, H F J; Soares, R M; Su, C; Gennari, S M

2014-12-01

This study aimed to isolate and genotype T. gondii from Brazilian wildlife. For this purpose, 226 samples were submitted to mice bioassay and screened by PCR based on 18S rRNA sequences. A total of 15 T. gondii isolates were obtained, including samples from four armadillos (three Dasypus novemcinctus, one Euphractus sexcinctus), three collared anteaters (Tamandua tetradactyla), three whited-lipped peccaries (Tayassu pecari), one spotted paca (Cuniculus paca), one oncilla (Leopardus tigrinus), one hoary fox (Pseudalopex vetulus), one lineated woodpecker (Dryocopus lineatus) and one maned wolf (Chrysocyon brachyurus). DNA from the isolates, originated from mice bioassay, and from the tissues of the wild animal, designated as "primary samples", were genotyped by PCR-restriction fragment length polymorphism (PCR/RFLP), using 12 genetic markers (SAG1, SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L258, PK1, CS3 and Apico). A total of 17 genotypes were identified, with 13 identified for the first time and four already reported in published literature. Results herein obtained corroborate previous studies in Brazil, confirming high diversity and revealing unique genotypes in this region. Given most of genotypes here identified are different from previous studies in domestic animals, future studies on T. gondii from wildlife is of interest to understand population genetics and structure of this parasite.

Genetic characterization of Toxoplasma gondii from Brazilian wildlife revealed abundant new genotypes

Directory of Open Access Journals (Sweden)

S.N. Vitaliano

2014-12-01

Full Text Available This study aimed to isolate and genotype T. gondii from Brazilian wildlife. For this purpose, 226 samples were submitted to mice bioassay and screened by PCR based on 18S rRNA sequences. A total of 15 T. gondii isolates were obtained, including samples from four armadillos (three Dasypus novemcinctus, one Euphractus sexcinctus, three collared anteaters (Tamandua tetradactyla, three whited-lipped peccaries (Tayassu pecari, one spotted paca (Cuniculus paca, one oncilla (Leopardus tigrinus, one hoary fox (Pseudalopex vetulus, one lineated woodpecker (Dryocopus lineatus and one maned wolf (Chrysocyon brachyurus. DNA from the isolates, originated from mice bioassay, and from the tissues of the wild animal, designated as “primary samples”, were genotyped by PCR–restriction fragment length polymorphism (PCR/RFLP, using 12 genetic markers (SAG1, SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L258, PK1, CS3 and Apico. A total of 17 genotypes were identified, with 13 identified for the first time and four already reported in published literature. Results herein obtained corroborate previous studies in Brazil, confirming high diversity and revealing unique genotypes in this region. Given most of genotypes here identified are different from previous studies in domestic animals, future studies on T. gondii from wildlife is of interest to understand population genetics and structure of this parasite.

Genotyping of Toxoplasma gondii and Sarcocystis spp. in road-killed wild mammals from the Central Western Region of the State of São Paulo, Brazil.

Science.gov (United States)

Richini-Pereira, Virgínia Bodelão; Marson, Pâmela Merlo; Silva, Rodrigo Costa da; Langoni, Helio

2016-01-01

Road-killed wild animals host zoonotic pathogens such as Toxoplasma gondii, offering a new opportunity for the epidemiological study of these infectious organisms. This investigation aimed to determine the presence of T. gondii and other apicomplexan parasites in tissue samples of 64 road-killed wild animals, using polymerase chain reaction (PCR). Positive samples were then typed by PCR-restriction fragment length polymorphism (RFLP) using 7 markers: SAG1, 5'-3'SAG2, SAG3, BTUB, c29-6, PK1, and Apico. PCR-RFLP targeting 18S ribosomal RNA (rRNA) genes was also performed on all samples to detect other apicomplexan parasites. T. gondii DNA was detected in 16 tissue samples from 8 individual animals, as follows: 1 Cerdocyon thous (crab-eating fox), 1 Didelphis albiventris (white-eared opossum), 1 Lutreolina crassicaudata (lutrine opossum), 2 Myrmecophaga tridactyla (giant anteater), 1 Procyon cancrivorus (crab-eating raccoon), and 2 Sphiggurus spinosus (Paraguay hairy dwarf porcupine). Seven different T. gondii genotypes were identified, 6 of which were novel. Typing by 18S rRNA verified these 16 T. gondii-infected samples, and identified 1 Sarcocystis spp.-infected animal [Dasypus novemcinctus (nine-banded armadillo)]. The amplified T. gondii (GenBank accession No. L37415.1) and Sarcocystis spp. 18S rRNA products were confirmed by sequencing. Our results indicate that T. gondii is commonly present in wild mammals, which act as sources of infection for humans and animals, including other wild species. The approach employed herein proved useful for detecting T. gondii and Sarcocystis spp. in the environment and identifying their natural reservoirs, contributing to our understanding of host-parasite interactions.

Genotyping of Toxoplasma gondii and Sarcocystis spp. in road-killed wild mammals from the Central Western Region of the State of São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Virgínia Bodelão Richini-Pereira

Full Text Available Abstract INTRODUCTION: Road-killed wild animals host zoonotic pathogens such as Toxoplasma gondii, offering a new opportunity for the epidemiological study of these infectious organisms. METHODS This investigation aimed to determine the presence of T. gondii and other apicomplexan parasites in tissue samples of 64 road-killed wild animals, using polymerase chain reaction (PCR. Positive samples were then typed by PCR-restriction fragment length polymorphism (RFLP using 7 markers: SAG1, 5′-3′SAG2, SAG3, BTUB, c29-6, PK1, and Apico. PCR-RFLP targeting 18S ribosomal RNA (rRNA genes was also performed on all samples to detect other apicomplexan parasites. RESULTS T. gondii DNA was detected in 16 tissue samples from 8 individual animals, as follows: 1 Cerdocyon thous (crab-eating fox, 1 Didelphis albiventris (white-eared opossum, 1 Lutreolina crassicaudata (lutrine opossum, 2 Myrmecophaga tridactyla (giant anteater, 1 Procyon cancrivorus (crab-eating raccoon, and 2 Sphiggurus spinosus (Paraguay hairy dwarf porcupine. Seven different T. gondii genotypes were identified, 6 of which were novel. Typing by 18S rRNA verified these 16 T. gondii-infected samples, and identified 1 Sarcocystis spp.-infected animal [Dasypus novemcinctus (nine-banded armadillo]. The amplified T. gondii (GenBank accession No. L37415.1 and Sarcocystis spp. 18S rRNA products were confirmed by sequencing. CONCLUSIONS Our results indicate that T. gondii is commonly present in wild mammals, which act as sources of infection for humans and animals, including other wild species. The approach employed herein proved useful for detecting T. gondii and Sarcocystis spp. in the environment and identifying their natural reservoirs, contributing to our understanding of host-parasite interactions.

Molecular detection of Toxoplasma gondii in water samples from Scotland and a comparison between the 529bp real-time PCR and ITS1 nested PCR.

Science.gov (United States)

Wells, Beth; Shaw, Hannah; Innocent, Giles; Guido, Stefano; Hotchkiss, Emily; Parigi, Maria; Opsteegh, Marieke; Green, James; Gillespie, Simon; Innes, Elisabeth A; Katzer, Frank

2015-12-15

Waterborne transmission of Toxoplasma gondii is a potential public health risk and there are currently no agreed optimised methods for the recovery, processing and detection of T. gondii oocysts in water samples. In this study modified methods of T. gondii oocyst recovery and DNA extraction were applied to 1427 samples collected from 147 public water supplies throughout Scotland. T. gondii DNA was detected, using real time PCR (qPCR) targeting the 529bp repeat element, in 8.79% of interpretable samples (124 out of 1411 samples). The samples which were positive for T. gondii DNA originated from a third of the sampled water sources. The samples which were positive by qPCR and some of the negative samples were reanalysed using ITS1 nested PCR (nPCR) and results compared. The 529bp qPCR was the more sensitive technique and a full analysis of assay performance, by Bayesian analysis using a Markov Chain Monte Carlo method, was completed which demonstrated the efficacy of this method for the detection of T. gondii in water samples. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effect of Macrophage Migration Inhibitory Factor (MIF) in Human Placental Explants Infected with Toxoplasma gondii Depends on Gestational Age

Science.gov (United States)

de Oliveira Gomes, Angelica; de Oliveira Silva, Deise Aparecida; Silva, Neide Maria; de Freitas Barbosa, Bellisa; Franco, Priscila Silva; Angeloni, Mariana Bodini; Fermino, Marise Lopes; Roque-Barreira, Maria Cristina; Bechi, Nicoletta; Paulesu, Luana Ricci; dos Santos, Maria Célia; Mineo, José Roberto; Ferro, Eloisa Amália Vieira

2011-01-01

Because macrophage migration inhibitory factor (MIF) is a key cytokine in pregnancy and has a role in inflammatory response and pathogen defense, the objective of the present study was to investigate the effects of MIF in first- and third-trimester human placental explants infected with Toxoplasma gondii. Explants were treated with recombinant MIF, IL-12, interferon-γ, transforming growth factor-β1, or IL-10, followed by infection with T. gondii RH strain tachyzoites. Supernatants of cultured explants were assessed for MIF production. Explants were processed for morphologic analysis, immunohistochemistry, and real-time PCR analysis. Comparison of infected and stimulated explants versus noninfected control explants demonstrated a significant increase in MIF release in first-trimester but not third-trimester explants. Tissue parasitism was higher in third- than in first-trimester explants. Moreover, T. gondii DNA content was lower in first-trimester explants treated with MIF compared with untreated explants. However, in third-trimester explants, MIF stimulus decreased T. gondii DNA content only at the highest concentration of the cytokine. In addition, high expression of MIF receptor was observed in first-trimester placental explants, whereas MIF receptor expression was low in third-trimester explants. In conclusion, MIF was up-regulated and demonstrated to be important for control of T. gondii infection in first-trimester explants, whereas lack of MIF up-regulation in third-trimester placentas may be involved in higher susceptibility to infection at this gestational age. PMID:21641401

DNA Amplification Techniques for the Detection of Toxoplasma gondii Tissue Cysts in Meat Producing Animals: A Narrative Review Article

Directory of Open Access Journals (Sweden)

Farooq RIAZ

2016-12-01

Full Text Available Background: Toxoplasma gondii is an intracellular parasite, which infects one-third population of world. Humans and animals acquire infection by ingesting oocytes from feces of cats or by meat of other animals having cysts that may lead to congenital, ocular or cephalic toxoplasmosis. Either it is important to detect T. gondii from meat of food animals from retail shops or directly at slaughterhouses, which is meant for export.Methods: The current research was done without time limitation using such terms as follows: “Toxoplasma gondii”, “Meat”, “Tissue cyst”, “PCR”, “LAMP”, “Screening” and “Immunological assay” alone or in combination, in English language. The used electronic databases for searching included as follows: PubMed, Scopus, Google Scholar, Web of Science and Science Direct. The searches were limited to the published papers to English language.Results: Sensitivity of different molecular techniques for diagnosis of Toxoplasma is real-time PCR > LAMP > conventional PCR. In addition to these DNA analysis tools, bioassay in mice and cats is considered as “gold standard” to detect T. gondii. Conclusion: This review article will help the readers for grasping advantages and limitations of different diagnostic tools for screening meat samples for T. gondii. This review also makes bibliography about the type of meat sample to be processed for diagnosis and different primers or sequences to be targeted for T. gondii by number of researches for its detection from meat or tissue sample using DNA amplification techniques.

Genetic diversity of Toxoplasma gondii isolates in Egyptian feral cats reveals new genotypes.

Science.gov (United States)

Al-Kappany, Y M; Rajendran, C; Abu-Elwafa, S A; Hilali, M; Su, C; Dubey, J P

2010-12-01

Cats are important in the epidemiology of Toxoplasma gondii because they are the only hosts that excrete environmentally resistant oocysts in feces. In the present study, 115 viable T. gondii isolates from tissues of cats from Egypt were genotyped using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) and DNA from tachyzoites. Seven genotypes were recognized including the clonal Type II, Type III (2 genotypes), and 4 atypical genotypes. Ninety percent (103 of 115) of isolates were clonal, i.e., Type II (n  =  61) and Type III (n  =  42) strains. Of the 61 Type II strains, all had the Type II alleles at all loci, except for 2 strains that had allele I at Apico. Eight isolates were divided into 4 atypical genotypes. One of these genotypes (with 4 isolates) was previously reported in dogs from Sri Lanka and in sand cats from the United Arab Emirates. Four isolates had mixed infections. These results revealed a strong clonal population structure with the dominance of clonal Type II and III lineages of T. gondii in feral cats from Egypt.

Detection of Toxoplasma gondii and Epstein-Barr virus in HIV patients with clinical symptoms of suspected central nervous system infection using duplex real-time polymerase chain reaction

Science.gov (United States)

Rahmawati, E.; Ibrahim, F.; Imran, D.; Sudarmono, P.

2017-08-01

Focal brain lesion is a neurological complication in HIV, which is marked as a space occupying lesion (SOL) and needs rapid and effective treatment. This lesion is mainly caused by encephalitis toxoplasma and primary central nervous system lymphoma related to the Epstein-Barr virus (EBV) infection, which is difficult to distinguish using CT scan or magnetic resonance imaging (MRI). The gold standard of diagnosing focal brain lesion has been brain biopsy, but this examination is an invasive procedure that causes complications. The objective of this study is to obtain the rapid laboratory diagnosis of Toxoplasma gondii (T. gondii) and EBV infection. In this experimental study, blood and cerebrospinal fluid were obtained from HIV patients who were admitted to the Neurology Department of Cipto Mangunkusumo Hospital. The samples were examined using duplex real-time polymerase chain reaction (PCR) to detect T. gondii and EBV. The first step was the optimization of duplex real-time PCR, including the annealing temperature, primer and probe concentration, elution volume, and template volume. Minimal DNA detection was used to measure minimal T. gondii and EBV. Cross reactions were determined for technical specificity using the bacteria and viruses Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa, Mycobacterium tuberculosis H37Rv, Candida spp, cytomegalovirus, herpes zoster virus, and varicella zoster virus. Duplex real-time PCR was applied optimally to patients. In the optimization of duplex real-time PCR, the annealing temperature of T. gondii and EBV were 58 °C, the concentration of primer forward and reverse for T. gondii and EBV were 0.2 μM, the concentration of probe for T. gondii and EBV were 0.4μM and 0.2 μM, respectively. Minimal DNA detection of T. gondii and EBV were 5.68 copy/ml and 1.31 copy/ml, respectively. There was no cross reaction between another bacteria and virus that were used as the primer and probe for T. gondii and EBV. The

[Serological Investigation of Toxoplasma gondii on Pregnant Women and Toxoplasmosis Suspected Patients Between 2012-2014 Years on a Tertiary Training Hospital].

Science.gov (United States)

Selek, Mehmet Burak; Bektöre, Bayhan; Baylan, Orhan; Özyurt, Mustafa

2015-09-01

Toxoplasmosis is a zoonotic disease which is still an important health issue in both developing and developed countries. We aimed to evaluate Toxoplasma gondii (T. gondii) seropositivity on toxoplasmosis suspected patients and pregnant women, retrospectively. Blood samples taken from toxoplasmosis suspected patients (n=1296) and pregnant women (1737) on our tertiary training hospital between 2012-2014 years. Anti-T. gondii IgG and IgM seropositivity analyzed with chemiluminescent microparticle immunological assay (CMIA) method. Also IgG avidity index were evaluated on patients who had both antibodies. Of 1269 toxoplasmosis suspected patients, 37% (n=479) had only T. gondii IgG positive while 1.9% (n=25) had both IgG and IgM antibodies. Of 1737 pregnant women, 24.2% (n=421) had only T. gondii IgG positive while 0.7% (n=13) of women were found positive for both antibodies. None of the total 3033 patients were seropositive for sole IgG antibody. Avidity tests were applied to the double positive patients and low avidity were detected on only one person from each group. Nationwide, high throughput, systemic seroprevalance studies is needed in order to take precautions for the public health to protect sensitive groups and pregnant women especially because of congenital toxoplasmosis risk.

Recombinant vaccines against T. gondii: comparison between homologous and heterologous vaccination protocols using two viral vectors expressing SAG1.

Science.gov (United States)

Mendes, Érica Araújo; Fonseca, Flavio G; Casério, Bárbara M; Colina, Janaína P; Gazzinelli, Ricardo Tostes; Caetano, Braulia C

2013-01-01

The use of recombinant viral vectors expressing T. gondii antigens is a safe and efficient approach to induce immune response against the parasite and a valuable tool for vaccine development. We have previously protected mice from toxoplasmosis by immunizing the animals with an adenovirus expressing the protein SAG1 (AdSAG1) of T. gondii. We are now looking for ways to improve the vaccination strategy and enhance protection. One limitation of homologous vaccinations (sequential doses of the same vector) is induction of anti-vector immune response that blocks cell transduction, restricts transgene expression and, consequently, compromises the overall outcome of vaccination. One way to avert the effects of anti-vector response is to use different viruses in prime and boost (heterologous vaccination). Bearing this in mind, we generated a modified Vaccinia Virus Ankara encoding SAG1 (MVASAG1), to be tested as boost agent after prime with AdSAG1. Although minor differences were observed in the magnitude of the anti-SAG1 immune response induced by each vaccination protocol, the heterologous immunization with AdSAG1 followed by MVASAG1 resulted in improved capacity to control brain cyst formation in a model of chronic toxoplasmosis in C57BL/6 mice.

Recombinant vaccines against T. gondii: comparison between homologous and heterologous vaccination protocols using two viral vectors expressing SAG1.

Directory of Open Access Journals (Sweden)

Érica Araújo Mendes

Full Text Available The use of recombinant viral vectors expressing T. gondii antigens is a safe and efficient approach to induce immune response against the parasite and a valuable tool for vaccine development. We have previously protected mice from toxoplasmosis by immunizing the animals with an adenovirus expressing the protein SAG1 (AdSAG1 of T. gondii. We are now looking for ways to improve the vaccination strategy and enhance protection. One limitation of homologous vaccinations (sequential doses of the same vector is induction of anti-vector immune response that blocks cell transduction, restricts transgene expression and, consequently, compromises the overall outcome of vaccination. One way to avert the effects of anti-vector response is to use different viruses in prime and boost (heterologous vaccination. Bearing this in mind, we generated a modified Vaccinia Virus Ankara encoding SAG1 (MVASAG1, to be tested as boost agent after prime with AdSAG1. Although minor differences were observed in the magnitude of the anti-SAG1 immune response induced by each vaccination protocol, the heterologous immunization with AdSAG1 followed by MVASAG1 resulted in improved capacity to control brain cyst formation in a model of chronic toxoplasmosis in C57BL/6 mice.

AN EVALUATION STUDY OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) USING RECOMBINANT PROTEIN GRA1 FOR DETECTION OF IgG ANTIBODIES AGAINTS TOXOPLASMA GONDII INFECTIONS

OpenAIRE

Muflikhah, Nina Difla; Artama, Wayan Tunas

2017-01-01

Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an intracellular protozoan parasite that live inside the cells of the reticulo endothelial and parenchymal cells of human and animals (mammals and birds). Some cases of toxoplasmosis usually have no symptoms, but in any cases caused severe symptoms, such as hydrocephalus, microcephalus, intracranial calcification, retinal damage, brain abscess, mental retardation, lymphadenopathy, and others. Its severe symptoms usually showe...

Evidence of feline immunodeficiency virus, feline leukemia virus, and Toxoplasma gondii in feral cats on Mauna Kea, Hawaii

Science.gov (United States)

Danner, R.M.; Goltz, Dan M.; Hess, S.C.; Banko, P.C.

2007-01-01

We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats (Felis catus) on Mauna Kea Hawaii from April 2002 to May 2004. Six of 68 (8.8%) and 11 of 68 (16.2%) cats were antibody positive to FIV and antigen positive for FeLV, respectively; 25 of 67 (37.3%) cats were seropositive to T. gondii. Antibodies to FeLV and T. gondii occurred in all age and sex classes, but FIV occurred only in adult males. Evidence of current or previous infections with two of these infectious agents was detected in eight of 64 cats (12.5%). Despite exposure to these infectious agents, feral cats remain abundant throughout the Hawaiian Islands. ?? Wildlife Disease Association 2007.

Seroprevalence of Toxoplasma gondii infection in goats and sheep in Zimbabwe

DEFF Research Database (Denmark)

Hove, T.; Lind, Peter; Mukaratirwa, S.

2005-01-01

Seroprevalence rates of Toxoplasma gondii anti-antibodies in adult goats and sheep from different parts of Zimbabwe were determined. A total of 225 (67.9 %) of the 335 serum samples tested were positive for anti-T. gondii IgG antibodies with the indirect fluorescent antibody test. There were...... differences in antibody seroprevalences among communal land goats from the different agro-ecological zones (Natural regions IIb and III: 80 and 96.7%, respectively; Natural region IV: 65.9%; Natural region V: 45%; and Natural region III had a significantly higher seroprevalence than IV and V. The highest...... in sheep from a large commercial farm (10%) was significantly lower than that of sheep reared under the communal grazing system (80%). Overall, significantly higher proportions of seropositive animals had antibody titres of 1:50 (34.2% of 225) and 1:100 (44% of 225) as compared to the 9.8% and 12...

Prevalence of Toxoplasma gondii antibodies in domestic donkeys (Equus asinus) in Durango, Mexico slaughtered for human consumption

OpenAIRE

Alvarado-Esquivel, Cosme; Alvarado-Esquivel, Domingo; Dubey, Jitender P

2015-01-01

Background Nothing is known about Toxoplasma gondii prevalence in donkeys in Mexico. Meat from donkey is consumed by humans in Mexico and also exported to other countries. We sought to determine the presence of antibodies against T. gondii in 239 domestic donkeys (Equus asinus) for slaughter in Durango, Mexico using the modified agglutination test (MAT). Donkeys were sampled in four premises (trade centers) where donkeys were gather for shipment to abattoirs in other Mexican states. Results A...

Toxoplasma gondii infection in meat animals from Africa: Systematic review and meta-analysis of sero-epidemiological studies

Directory of Open Access Journals (Sweden)

Aretas Babatoundé Nounnagnon Tonouhewa

2017-02-01

Full Text Available Aim: Toxoplasma gondii is an ubiquitous apicomplexan parasite which causes toxoplasmosis in humans and animals. Felids especially cats are definitive hosts and almost all warm-blooded mammals, including livestock and human can serve as intermediate hosts. Food animals can be reservoirs for T. gondii and act as one of the sources for parasite transmission to humans. The objective of this study is to collect serological data on the prevalence of anti-T. gondii antibody, and risk factors for certain food animals from Africa to provide a quantitative estimate of T. gondii infection among these species from different African countries. Materials and Methods: Four databases were used to search seroepidemiological data on the prevalence of anti-T. gondii antibody in food animals between 1969 and 2016 from African countries. The search focused on data obtained by serologic test in food animals and meta-analyses were performed per species. Results: A total of 30,742 individual samples from 24 countries, described in 68 articles were studied. The overall estimated prevalence for toxoplasmosis in chicken, camel, cattle, sheep, goat, pig were 37.4% (29.2-46.0%, 36% (18-56%, 12% (8-17%, 26.1% (17.0-37.0%, 22.9% (12.3-36.0%, and 26.0% (20-32.0%, respectively. Moreover, major risk factor of infection was age, farming system, and farm location. Conclusions: A significant variation in the seroepidemiological data was observed within each species and country. The results can aid in an updated epidemiological analysis but also can be used as an important input in quantitative microbial risk assessment models. Further studies are required for a better and continual evaluation of the occurrence of this zoonotic infection.