Anionic Sites, Fucose Residues and Class I Human Leukocyte Antigen Fate During Interaction of Toxoplasma gondii with Endothelial Cells

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Stumbo Ana Carolina

2002-01-01

Full Text Available Toxoplasma gondii invades and proliferates in human umbilical vein endothelial cells where it resides in a parasitophorous vacuole. In order to analyze which components of the endothelial cell plasma membrane are internalized and become part of the parasitophorous vacuole membrane, the culture of endothelial cells was labeled with cationized ferritin or UEA I lectin or anti Class I human leukocytte antigen (HLA before or after infection with T. gondii. The results showed no cationized ferritin and UEA I lectin in any parasitophorous vacuole membrane, however, the Class I HLA molecule labeling was observed in some endocytic vacuoles containing parasite until 1 h of interaction with T. gondii. After 24 h parasite-host cell interaction, the labeling was absent on the vacuolar membrane, but presents only in small vesicles near parasitophorous vacuole. These results suggest the anionic site and fucose residues are excluded at the time of parasitophorous vacuole formation while Class I HLA molecules are present only on a minority of Toxoplasma-containig vacuoles.

Neutrophils, dendritic cells and Toxoplasma.

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Denkers, Eric Y; Butcher, Barbara A; Del Rio, Laura; Bennouna, Soumaya

2004-03-09

Toxoplasma gondii rapidly elicits strong Type 1 cytokine-based immunity. The necessity for this response is well illustrated by the example of IFN-gamma and IL-12 gene knockout mice that rapidly succumb to the effects of acute infection. The parasite itself is skilled at sparking complex interactions in the innate immune system that lead to protective immunity. Neutrophils are one of the first cell types to arrive at the site of infection, and the cells release several proinflammatory cytokines and chemokines in response to Toxoplasma. Dendritic cells are an important source of IL-12 during infection with T. gondii and other microbial pathogens, and they are also specialized for high-level antigen presentation to T lymphocytes. Tachyzoites express at least two types of molecules that trigger innate immune cell cytokine production. One of these involves Toll-like receptor/MyD88 pathways common to many microbial pathogens. The second pathway is less conventional and involves molecular mimicry between a parasite cyclophilin and host CC chemokine receptor 5-binding ligands. Neutrophils, dendritic cells and Toxoplasma work together to elicit the immune response required for host survival. Cytokine and chemokine cross-talk between parasite-triggered neutrophils and dendritic cells results in recruitment, maturation and activation of the latter. Neutrophil-empowered dendritic cells possess properties expected of highly potent antigen presenting cells that drive T helper 1 generation.

P35 and P22 Toxoplasma gondii antigens abbreviate regions to diagnose acquired toxoplasmosis during pregnancy: toward single-sample assays.

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Costa, Juan G; Peretti, Leandro E; García, Valeria S; Peverengo, Luz; González, Verónica D G; Gugliotta, Luis M; Dalla Fontana, Maria L; Lagier, Claudia M; Marcipar, Iván S

2017-03-01

P35 and P22 Toxoplasma gondii proteins are recognized by specific IgG at the early infection stage, making them ideal for acute toxoplasmosis pregnancy control. Both proteins have been studied to discriminate between acute and chronic toxoplasmosis. However, results were hardly comparable because different protein obtainment procedures led to different antigens, the reference panels used were not optimally typified, and avidity tests were either not performed or narrowly examined. We bioinformatically predicted P35 and P22 regions with the highest density of epitopes, and expressed them in pET32/BL21DE3 alternative expression system, obtaining the soluble proteins rP35a and rP22a. We assessed their diagnostic performance using pregnant woman serum samples typified as: not infected, NI (IgG-, IgM-), typical-chronic, TC (IgM-, IgG+), presumably acute, A (IgG+, IgM+, low-avidity IgG), and recently chronic, RC (IgG+, IgM+, high-avidity IgG). rP35a performed better than rP22a to differentiate A from RC, the areas under the curve (AUC) being 0.911 and 0.818, respectively. They, however, performed similarly to differentiate A from TC+RC (AUC: 0.915 and 0.907, respectively). rP35a and rP22a evaluation by avidity ELISA to discriminate A from RC rendered AUC values of 0.974 and 0.921, respectively. The indirect ELISA and avidity ELISA results analyzed in tandem were consistent with those obtained using commercial kits. rP35a and rP22a features suggest that, with complementary use, they could replace parasite lysate for toxoplasmosis infection screening and for acute toxoplasmosis diagnosis. Our proposal should be validated by a longitudinal study and may lead to a reliable toxoplasmosis pregnancy control, performing tests in only one serum sample.

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

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

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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†

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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

The time course of the specific antibody response by various ELISAs in pigs experimentally infected with Toxoplasma gondii

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Lind, Peter; Haugegaard, J.; Wingstrand, Anne

1997-01-01

With the aim of developing routine serological tests for monitoring the Toxoplasma infection status of Danish swine herds, four ELISAs based on tachyzoite antigen were set up: (1) an indirect ELISA for IgG-antibody; (2) a blocking ELISA for antibody to the membrane antigen, P-30; (3) an indirect ...

Determination of Immunogenic Relevant Antigens in the Excretory-Secretory (ES Products and the Lysates of Ascaridia galli Larvae

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S Saffi

2008-04-01

Full Text Available Background: Ascaridia galli, the largest nematode of small intestine of birds, especially the native poultry, may give rise to serious illness, pathological defects and economical losses even in modern poultry production systems. Although various measures have been undertaken to vaccinate poultry against A.galli, no satisfactory results were obtained so far. However, there is no report on the efficacy of excretory-secretory (ES proteins of A.galli larvae in immunization of poultry. Thus, the aim of the present research project was based on the use of the ES products of the larvae, in order to find the protective anti­gens.Methods: Five hundred native poultry were autopsied and adult A.galli was removed form their intestines. The eggs were harvested form the uterus of female worms and cultured at 25 ˚C in water containing 0.1 N sulphuric acid for almost a fort­night. The larvae were then freed mechanically and kept in Earl's salt solution for a few days. The supernatant solution of alive larvae containing the ES products of the larvae, as well as the sonicated alive and dead larvae, was analyzed by SDS-PAGE.Result: Many protein fractions of 15 kDa up to 200 kDa were demonstrated in lysate of these larvae. Using the serum of a hen, infected with a high numbers of A.galli, an immunogenic antigen was identified between 55 kDa to 72 kDa by Western blotting procedure.Conclusion: Finding the protein band between 55 and 72 kDa can be promising for preparation of vaccine, though more investigations are needed to prove the protective ability of this antigen.

Autologous Dendritic Cells Pulsed with Allogeneic Tumor Cell Lysate in Mesothelioma: From Mouse to Human.

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Aerts, Joachim G J V; de Goeje, Pauline L; Cornelissen, Robin; Kaijen-Lambers, Margaretha E H; Bezemer, Koen; van der Leest, Cor H; Mahaweni, Niken M; Kunert, André; Eskens, Ferry A L M; Waasdorp, Cynthia; Braakman, Eric; van der Holt, Bronno; Vulto, Arnold G; Hendriks, Rudi W; Hegmans, Joost P J J; Hoogsteden, Henk C

2018-02-15

Purpose: Mesothelioma has been regarded as a nonimmunogenic tumor, which is also shown by the low response rates to treatments targeting the PD-1/PD-L1 axis. Previously, we demonstrated that autologous tumor lysate-pulsed dendritic cell (DC) immunotherapy increased T-cell response toward malignant mesothelioma. However, the use of autologous tumor material hampers implementation in large clinical trials, which might be overcome by using allogeneic tumor cell lines as tumor antigen source. The purpose of this study was to investigate whether allogeneic lysate-pulsed DC immunotherapy is effective in mice and safe in humans. Experimental Design: First, in two murine mesothelioma models, mice were treated with autologous DCs pulsed with either autologous or allogeneic tumor lysate or injected with PBS (negative control). Survival and tumor-directed T-cell responses of these mice were monitored. Results were taken forward in a first-in-human clinical trial, in which 9 patients were treated with 10, 25, or 50 million DCs per vaccination. DC vaccination consisted of autologous monocyte-derived DCs pulsed with tumor lysate from five mesothelioma cell lines. Results: In mice, allogeneic lysate-pulsed DC immunotherapy induced tumor-specific T cells and led to an increased survival, to a similar extent as DC immunotherapy with autologous tumor lysate. In the first-in-human clinical trial, no dose-limiting toxicities were established and radiographic responses were observed. Median PFS was 8.8 months [95% confidence interval (CI), 4.1-20.3] and median OS not reached (median follow-up = 22.8 months). Conclusions: DC immunotherapy with allogeneic tumor lysate is effective in mice and safe and feasible in humans. Clin Cancer Res; 24(4); 766-76. ©2017 AACR . ©2017 American Association for Cancer Research.

Toxoplasma gondii infection shifts dendritic cells into an amoeboid rapid migration mode encompassing podosome dissolution, secretion of TIMP-1, and reduced proteolysis of extracellular matrix.

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Ólafsson, Einar B; Varas-Godoy, Manuel; Barragan, Antonio

2018-03-01

Dendritic cells (DCs) infected by Toxoplasma gondii rapidly acquire a hypermigratory phenotype that promotes systemic parasite dissemination by a "Trojan horse" mechanism in mice. Recent paradigms of leukocyte migration have identified the amoeboid migration mode of DCs as particularly suited for rapid locomotion in extracellular matrix and tissues. Here, we have developed a microscopy-based high-throughput approach to assess motility and matrix degradation by Toxoplasma-challenged murine and human DCs. DCs challenged with T. gondii exhibited dependency on metalloproteinase activity for hypermotility and transmigration but, strikingly, also dramatically reduced pericellular proteolysis. Toxoplasma-challenged DCs up-regulated expression and secretion of tissue inhibitor of metalloproteinases-1 (TIMP-1) and their supernatants impaired matrix degradation by naïve DCs and by-stander DCs dose dependently. Gene silencing of TIMP-1 by short hairpin RNA restored matrix degradation activity in Toxoplasma-infected DCs. Additionally, dissolution of podosome structures in parasitised DCs coincided with abrogated matrix degradation. Toxoplasma lysates inhibited pericellular proteolysis in a MyD88-dependent fashion whereas abrogated proteolysis persevered in Toxoplasma-infected MyD88-deficient DCs. This indicated that both TLR/MyD88-dependent and TLR/MyD88-independent signalling pathways mediated podosome dissolution and the abrogated matrix degradation. We report that increased TIMP-1 secretion and cytoskeletal rearrangements encompassing podosome dissolution are features of Toxoplasma-induced hypermigration of DCs with an impact on matrix degradation. Jointly, the data highlight how an obligate intracellular parasite orchestrates key regulatory cellular processes consistent with non-proteolytic amoeboid migration of the vehicle cells that facilitate its dissemination. © 2017 John Wiley & Sons Ltd.

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

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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.

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 ...

Immunological Characterization of Whole Tumour Lysate-Loaded Dendritic Cells for Cancer Immunotherapy

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Ottobrini, Luisa; Biasin, Mara; Borelli, Manuela; Lucignani, Giovanni; Trabattoni, Daria; Clerici, Mario

2016-01-01

Introduction Dendritic cells play a key role as initiators of T-cell responses, and even if tumour antigen-loaded dendritic cells can induce anti-tumour responses, their efficacy has been questioned, suggesting a need to enhance immunization strategies. Matherials & Methods We focused on the characterization of bone marrow-derived dendritic cells pulsed with whole tumour lysate (TAA-DC), as a source of known and unknown antigens, in a mouse model of breast cancer (MMTV-Ras). Dendritic cells were evaluated for antigen uptake and for the expression of MHC class I/II and costimulatory molecules and markers associated with maturation. Results Results showed that antigen-loaded dendritic cells are characterized by a phenotypically semi-mature/mature profile and by the upregulation of genes involved in antigen presentation and T-cell priming. Activated dendritic cells stimulated T-cell proliferation and induced the production of high concentrations of IL-12p70 and IFN-γ but only low levels of IL-10, indicating their ability to elicit a TH1-immune response. Furthermore, administration of Antigen loaded-Dendritic Cells in MMTV-Ras mice evoked a strong anti-tumour response in vivo as demonstrated by a general activation of immunocompetent cells and the release of TH1 cytokines. Conclusion Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer. PMID:26795765

Vaccination with melanoma lysate-pulsed dendritic cells, of patients with advanced colorectal carcinoma: report from a phase I study

DEFF Research Database (Denmark)

Burgdorf, S K; Fischer, A; Claesson, M H

2006-01-01

Immune therapy have shown new and exciting perspectives for cancer treatment. Aim of our study was to evaluate toxicity and possible adverse effects from vaccination of patients with advanced colorectal cancer with autologous dendritic cells (DC) pulsed with lysate from a newly developed melanoma...... contained 3-5 x 10(6) DCs. Five of the six patients received all five vaccines. The treatment was well tolerated in all patients without any observed vaccine-correlated adverse effects. Treatment with this DC-based cancer vaccine proved safe and non-toxic.......Immune therapy have shown new and exciting perspectives for cancer treatment. Aim of our study was to evaluate toxicity and possible adverse effects from vaccination of patients with advanced colorectal cancer with autologous dendritic cells (DC) pulsed with lysate from a newly developed melanoma...... and selected melanoma cell line enriched in expression of MAGE-A antigens and deficient in expression of melanoma differentiation antigens: tyrosinase, MART-1 and gp100. Vaccinations were administered intradermally on the proximal thigh with a total of five given vaccines at 2 weeks intervals. Each vaccine...

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

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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.

Precision cancer immunotherapy: optimizing dendritic cell-based strategies to induce tumor antigen-specific T-cell responses against individual patient tumors.

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Osada, Takuya; Nagaoka, Koji; Takahara, Masashi; Yang, Xiao Yi; Liu, Cong-Xiao; Guo, Hongtao; Roy Choudhury, Kingshuk; Hobeika, Amy; Hartman, Zachary; Morse, Michael A; Lyerly, H Kim

2015-05-01

Most dendritic cell (DC)-based vaccines have loaded the DC with defined antigens, but loading with autologos tumor-derived antigens would generate DCs that activate personalized tumor-specific T-cell responses. We hypothesized that DC matured with an optimized combination of reagents and loaded with tumor-derived antigens using a clinically feasible electroporation strategy would induce potent antitumor immunity. We first studied the effects on DC maturation and antigen presentation of the addition of picibanil (OK432) to a combination of zoledronic acid, tumor necrosis factor-α, and prostaglandin E2. Using DC matured with the optimized combination, we tested 2 clinically feasible sources of autologous antigen for electroloading, total tumor mRNA or total tumor lysate, to determine which stimulated more potent antigen-specific T cells in vitro and activated more potent antitumor immunity in vivo. The combination of tumor necrosis factor-α/prostaglandin E2/zoledronic acid/OK432 generated DC with high expression of maturation markers and antigen-specific T-cell stimulatory function in vitro. Mature DC electroloaded with tumor-derived mRNA [mRNA electroporated dendritic cell (EPDC)] induced greater expansion of antigen-specific T cells in vitro than DC electroloaded with tumor lysate (lysate EPDC). In a therapeutic model of MC38-carcinoembryonic antigen colon cancer-bearing mice, vaccination with mRNA EPDC induced the most efficient anti-carcinoembryonic antigen cellular immune response, which significantly suppressed tumor growth. In conclusion, mature DC electroloaded with tumor-derived mRNA are a potent cancer vaccine, especially useful when specific tumor antigens for vaccination have not been identified, allowing autologous tumor, and if unavailable, allogeneic cell lines to be used as an unbiased source of antigen. Our data support clinical testing of this strategy.

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

NARCIS (Netherlands)

Weinert, Brian T.; Krishnadath, Kausilia K.; Milano, Francesca; Pedersen, Ayako W.; Claesson, Mogens H.; Zocca, Mai-Britt

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated

An experimental protocol for the establishment of dogs with long-term cellular immune reactions to Leishmania antigens

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Márcia Cristina Aquino Teixeira

2011-03-01

Full Text Available Domestic dogs are considered to be the main reservoirs of zoonotic visceral leishmaniasis. In this work, we evaluated a protocol to induce Leishmania infantum/Leishmania chagasi-specific cellular and humoral immune responses in dogs, which consisted of two injections of Leishmania promastigote lysate followed by a subcutaneous inoculation of viable promastigotes. The primary objective was to establish a canine experimental model to provide positive controls for testing immune responses to Leishmania in laboratory conditions. After inoculation of viable promastigotes, specific proliferative responses of peripheral blood mononuclear cells (PBMCs to either Leishmania lysate or recombinant proteins, the in vitro production of interferon-γ by antigen-stimulated PBMCs and a significant increase in circulating levels of anti-Leishmania antibodies were observed. The immunized dogs also displayed positive delayed-type hypersensitivity reactions to Leishmania crude antigens and to purified recombinant proteins. An important finding that supports the suitability of the dogs as positive controls is that they remained healthy for the entire observation period, i.e., more than seven years after infection. Following the Leishmania antigen lysate injections, the infection of dogs by the subcutaneous route appears to induce a sustained cellular immune response, leading to an asymptomatic infection. This provides a useful model for both the selection of immunogenic Leishmania antigens and for immunobiological studies on their possible immunoprotective activities.

Ubiquitinated Proteins Isolated From Tumor Cells Are Efficient Substrates for Antigen Cross-Presentation.

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Yu, Guangjie; Moudgil, Tarsem; Cui, Zhihua; Mou, Yongbin; Wang, Lixin; Fox, Bernard A; Hu, Hong-Ming

2017-06-01

We have previously shown that inhibition of the proteasome causes defective ribosomal products to be shunted into autophagosomes and subsequently released from tumor cells as defective ribosomal products in Blebs (DRibbles). These DRibbles serve as an excellent source of antigens for cross-priming of tumor-specific T cells. Here, we examine the role of ubiquitinated proteins (Ub-proteins) in this pathway. Using purified Ub-proteins from tumor cells that express endogenous tumor-associated antigen or exogenous viral antigen, we tested the ability of these proteins to stimulate antigen-specific T-cell responses, by activation of monocyte-derived dendritic cells generated from human peripheral blood mononuclear cells. Compared with total cell lysates, we found that purified Ub-proteins from both a gp100-specific melanoma cell line and from a lung cancer cell line expressing cytomegalovirus pp65 antigen produced a significantly higher level of IFN-γ in gp100- or pp65-specific T cells, respectively. In addition, Ub-proteins from an allogeneic tumor cell line could be used to stimulate tumor-infiltrating lymphocytes isolated and expanded from non-small cell lung cancer patients. These results establish that Ub-proteins provide a relevant source of antigens for cross-priming of antitumor immune responses in a variety of settings, including endogenous melanoma and exogenous viral antigen presentation, as well as antigen-specific tumor-infiltrating lymphocytes. Thus, ubiquitin can be used as an affinity tag to enrich for unknown tumor-specific antigens from tumor cell lysates to stimulate tumor-specific T cells ex vivo or to be used as vaccines to target short-lived proteins.

Antigenic evaluation of a recombinant baculovirus-expressed Sarcocystis neurona SAG1 antigen.

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Gupta, G D; Lakritz, J; Saville, W J; Livingston, R S; Dubey, J P; Middleton, J R; Marsh, A E

2004-10-01

Sarcocystis neurona is the primary parasite associated with equine protozoal myeloencephalitis (EPM). This is a commonly diagnosed neurological disorder in the Americas that infects the central nervous system of horses. Current serologic assays utilize culture-derived parasites as antigen. This method requires large numbers of parasites to be grown in culture, which is labor intensive and time consuming. Also, a culture-derived whole-parasite preparation contains conserved antigens that could cross-react with antibodies against other Sarcocystis species and members of Sarcocystidae such as Neospora spp., Hammondia spp., and Toxoplasma gondii. Therefore, there is a need to develop an improved method for the detection of S. neurona-specific antibodies. The sera of infected horses react strongly to surface antigen 1 (SnSAG1), an approximately 29-kDa protein, in immunoblot analysis, suggesting that it is an immunodominant antigen. The SnSAG1 gene of S. neurona was cloned, and recombinant S. neurona SAG1 protein (rSnSAG1-Bac) was expressed with the use of a baculovirus system. By immunoblot analysis, the rSnSAG1-Bac antigen detected antibodies to S. neurona from naturally infected and experimentally inoculated equids, cats, rabbit, mice, and skunk. This is the first report of a baculovirus-expressed recombinant S. neurona antigen being used to detect anti-S. neurona antibodies in a variety of host species.

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

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Italmar Teodorico Navarro

1998-09-01

inoculum and 4x10(7 (second inoculum - 35 days later, except for strain VPS, where one cat died 10 days after the first inoculation and another showed symptoms of acute toxoplasmosis. In all other strains, no clinical signs were detected during 6 months of observation. The antibody response after immunization was monitored by indirect immunofluorescence (IF test by the use of anti-cat IgG conjugate. The antibody titers obtained at the 20th day varied from 1:1,024 to 1:4,096 and from 1:1,024 to 1:8,000 at the 40th day. Only the VPS strain attained titers of 1:16,000 at the 30th day of immunization. Homologous and heterologos titers were equivalem without any difference among the strain. When the immune sera were adsorbed with live tachyzoites, a reduction in the antibody titers was demonstrated both in homologous and heterologous levels. These results suggest that although dijferences in virulence for cats are evident among the strains. The surface antigens are commom among the T. gondii strains on the basis of IF antibody level. The results also demonstrated that apparently there is no correlation between virulence and serological characteristics of the studied strains of Toxoplasma gondii. However the importance of the IF test in the laboratorial diagnosis of Toxoplasmosis is reinforced.

Vaccination with OK-432 followed by TC-1 tumor lysate leads to significant antitumor effects.

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Chen, I-Ju; Yen, Chih-Feng; Lin, Kun-Ju; Lee, Chyi-Long; Soong, Yung-Kuei; Lai, Chyong-Huey; Lin, Cheng-Tao

2011-07-01

Human papillomavirus (HPV) infects large numbers of women worldwide and is present in more than 99% of all cervical cancer. TC-1 cell is a cell line with high expression of E7 antigen of HPV type 16 and its cell lysate has been demonstrated as an ideal inducer of E7-specific, antitumor immunity. OK-432 (Picibanil), a penicillin-killed Streptococcus pyogenes, has been reported with potent immunomodulation properties in cancer treatment by stimulating the maturation of dendritic cells (DCs) and secretion of Th-1 type cytokines. The current study demonstrated that a protocol to immunize the C57BL/6 mice with OK-432 followed by treatment with TC-1 lysate can generate markedly increased immune responses of E7-specific CD4(+) T cells and a moderate increase of natural killer (NK) cell, as well as a satisfactorily protective and therapeutic antitumor effect by triggering the DCs to prime T cells. Depletion of lymphocyte subset in vivo suggested that the antitumor effects could be dominantly executed by CD8+ T cells and followed by NK cells, and both of these reactions were induced by the generation of robust E7-specific CD4(+) T helper cell response. These findings warrant OK-432 combination with tumor-lysate as an effective and safe vaccine in future clinical application of cervical cancer.

Clinical Benefit of Allogeneic Melanoma Cell Lysate-Pulsed Autologous Dendritic Cell Vaccine in MAGE-Positive Colorectal Cancer Patients

DEFF Research Database (Denmark)

Toh, Han Chong; Wang, Who-Whong; Chia, Whay Kuang

2009-01-01

PURPOSE: We evaluated the clinical benefit of an allogeneic melanoma cell lysate (MCL)-pulsed autologous dendritic cell (DC) vaccine in advanced colorectal cancer patients expressing at least one of six MAGE-A antigens overexpressed by the cell line source of the lysate. EXPERIMENTAL DESIGN: DCs...... were cultured from peripheral blood mononuclear cells (PBMC), pulsed with the allogeneic MCL, and matured using cytokines that achieved high CD83- and CCR7-expressing DCs. Each patient received up to 10 intradermal vaccinations (3-5 x 10(6) cells per dose) at biweekly intervals. RESULTS: Twenty......-free for >27 and >37 months, respectively. This result is particularly meaningful as all patients had progressive disease before treatment. Overall, DC vaccination was associated with a serial decline in regulatory T cells. Using an antibody array, we characterized plasma protein profiles in responding...

Compaction agent clarification of microbial lysates

Science.gov (United States)

DeWalt, Brad W.; Murphy, Jason C.; Fox, George E.; Willson, Richard C.

2003-01-01

Recombinant proteins are often purified from microbial lysates containing high concentrations of nucleic acids. Pre-purification steps such as nuclease addition or precipitation with polyethyleneimine or ammonium sulfate are normally required to reduce viscosity and to eliminate competing polyanions before anion exchange chromatography. We report that small polycationic compaction agents such as spermine selectively precipitate nucleic acids during or after Escherichia coli lysis, allowing DNA and RNA to be pelleted with the insoluble cell debris. Analysis by spectrophotometry and protein assay confirmed a significant reduction in the concentration of nucleic acids present, with preservation of protein. Lysate viscosity is greatly reduced, facilitating subsequent processing. We have used 5mM spermine to remove nucleic acids from E. coli lysate in the purification of a hexahistidine-tagged HIV reverse transcriptase.

Lifelong Persistence of Toxoplasma Cysts: A Questionable Dogma?

Science.gov (United States)

Rougier, Solène; Montoya, Jose G; Peyron, François

2017-02-01

It is believed that infection by Toxoplasma gondii triggers a lifelong protective immunity due to the persistence of parasitic cysts which induce immunoprotection against reinfection. A review of the scientific literature since the 1950s did not yield any definitive data regarding the duration of cysts in the host or the presence of lifelong protective immunity, which led us to question this dogma. We put forward the hypothesis that sustained immunity to T. gondii requires repeated antigenic stimulations. The decline of seroprevalence recently observed in many countries might contribute to explain the loss of immunity. We address the potential consequences of this phenomenon, should it persist and worsen. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of protective effect of multiantigenic DNA vaccine encoding MIC3 and ROP18 antigen segments of Toxoplasma gondii in mice.

Science.gov (United States)

Qu, Daofeng; Han, Jianzhong; Du, Aifang

2013-07-01

The high incidence and severe damage caused by Toxoplasma gondii infection clearly indicates the need for the development of a vaccine. In this study, we evaluated the immune responses and protection against toxoplasmosis by immunizing ICR mice with a multiantigenic DNA vaccine. To develop the multiantigenic vaccine, two T. gondii antigens, MIC3 and ROP18, selected on the basis of previous studies were chosen. ICR mice were immunized subcutaneously with PBS, empty pcDNA3.1 vector, pMIC3, pROP18, and pROP18-MIC3, respectively. The results of lymphocyte proliferation assay, cytokine, and antibody determinations showed that mice immunized with pROP18-MIC3 elicited stronger humoral and Th1-type cellular immune responses than those immunized with single-gene plasmids, empty plasmid, or phosphate-buffered saline. After a lethal challenge with the highly virulent T. gondii RH strain, a prolonged survival time in pROP18-MIC3-immunized mice was observed in comparison to control groups. Our study indicates that the introduction of multiantigenic DNA vaccine is more powerful and efficient than single-gene vaccine, and deserves further evaluation and development.

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

Antigen-Addicted T Cell Reserves Trickle Charge the Frontline Killers.

Science.gov (United States)

Kalia, Vandana; Sarkar, Surojit

2016-07-19

Highly active killer T cells mediate a stable standoff during controlled persistent infections. In this issue of Immunity, Robey and colleagues describe a unique antigen-addicted T cell population bearing characteristics of both effector and memory CD8(+) T cells that provides a continuous supply of potent killer T cells to curb Toxoplasma gondii growth during latency. Copyright © 2016 Elsevier Inc. All rights reserved.

Porcine platelet lysate as a supplement for animal cell culture

Science.gov (United States)

Aldén, Anna; Gonzalez, Lorena; Persson, Anna; Christensson, Kerstin; Holmqvist, Olov

2007-01-01

A novel supplementation of cell growth media based on a porcine platelet lysate was developed for culture of animal-derived cells. The platelet lysate was produced from porcine blood and contained lysate of platelets and plasma components. It showed satisfactory microbiological integrity and it carried only low amount of endotoxins (platelet lysate supported well proliferation of Vero (African green monkey transformed kidney epithelial cells), Chinese hamster ovary (CHO) and hybridoma cells comparable to fetal bovine serum (FBS). Platelet lysate shows promise as a viable choice over FBS as it can be produced in large quantities, high lot-to-lot consistency and with an attractive price structure. Furthermore it is a strong alternative to FBS for ethical reasons. It is expected that it can be used as a general supplementation for most animal cells for research studies on the proliferation of cells and their expression of products. PMID:19002989

Human leukocyte antigen-e alleles are associated with hepatitis c virus, torque teno virus, and toxoplasma co-infections but are not associated with hepatitis b virus, hepatitis d virus, and GB virus c co-infections in human immunodeficiency virus patients

Directory of Open Access Journals (Sweden)

Afiono Agung Prasetyo

2016-01-01

Full Text Available Context: Data regarding the distribution of Human Leukocyte Antigen (HLA-E alleles and their association with blood-borne pathogen infections/co-infections are limited for many populations, including Indonesia. Aims: The aim of this study was to analyze the association between HLA-E allelic variants and infection with blood-borne pathogens such as hepatitis B virus (HBV, hepatitis C virus (HCV, hepatitis D virus (HDV, torque teno virus (TTV, GB virus C (GBV-C, and Toxoplasma gondii (T. gondii in Indonesian Javanese human immunodeficiency virus (HIV patients. Settings and Design: A total of 320 anti-HIV-positive blood samples were analyzed for HBV, HCV, HDV, TTV, GBV-C, and T. gondii infection status and its association with HLA-E allelic variants. Materials and Methods: Nucleic acid was extracted from plasma samples and used for the molecular detection of HBV DNA, HCV RNA, HDV RNA, TTV DNA, and GBV-C RNA, whereas hepatitis B surface antigen, anti-HCV, immunoglobulin M and G (IgM and IgG anti-T. gondii were detected through serological testing. The blood samples were genotyped for HLA-E loci using a sequence-specific primer-polymerase chain reaction. Statistical Analysis Used: Either the Chi-square or Fisher′s exact test was performed to analyze the frequency of HLA-E alleles and blood-borne pathogen infections in the population. Odds ratios (ORs were calculated to measure the association between the antibodies found and the participants′ possible risk behaviors. A logistic regression analysis was used to assess the associations. Results: HLA-EFNx010101/0101 was associated with HCV/TTV co-infection (adjusted OR [aOR]: 3.5; 95% confidence interval [CI]: 1.156-10.734; P = 0.027 and IgM/IgG anti-Toxo positivity (aOR: 27.0; 95% CI: 3.626-200.472; P = 0.001. HLA-EFNx010103/0103 was associated with TTV co-infection (aOR: 2.7; 95% CI: 1.509-4.796; P = 0.001. Conclusions: HLA-E alleles in Indonesian Javanese HIV patients were found to be associated

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

DEFF Research Database (Denmark)

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

2004-01-01

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

Induction of partial protection against infection with Toxoplasma gondii genotype II by DNA vaccination with recombinant chimeric tachyzoite antigens

DEFF Research Database (Denmark)

Rosenberg, Carina Agerbo; De Craeye, S.; Jongert, E.

2009-01-01

Infection with the obligate intracellular parasite Toxoplasma gondii is a significant source of parasitic infections worldwide. In adults, infections may often lead to severe retinochoroiditis. Infection of the foetus causes abortion or congenital pathology that may lead to neurological complicat......Infection with the obligate intracellular parasite Toxoplasma gondii is a significant source of parasitic infections worldwide. In adults, infections may often lead to severe retinochoroiditis. Infection of the foetus causes abortion or congenital pathology that may lead to neurological...

Platelet lysate: a replacement for fetal bovine serum in animal cell culture?

OpenAIRE

Johansson, Liselott; Klinth, Jeanna; Holmqvist, Olov; Ohlson, Sten

2003-01-01

A new cell culture supplement, platelet lysate, was evaluated with reference to fetal bovine serum (FBS), an established industrial medium for animal cell culture. Chemical and bacteriological profiles were conducted including the presence of platelet-derived growth factor (PDGF). PDGF was detected in the platelet lysate but it was not present in FBS. The platelet lysate medium demonstrated lack of microorganisms, mycoplasma and endotoxins. The platelet lysate was investigated in culture stud...

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

DEFF Research Database (Denmark)

Weinert, Brian T; Krishnadath, Kausilia K; Milano, Francesca

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated...... in the production of the vaccine. Quantitative PCR was used to assay 74 tumor antigen genes in patients with squamous cell carcinoma of the esophagus. 81% (13/16) of tumors expressed more than five cancer/testis (CT) antigens. A total of 96 genes were assayed in the tumor cell clone (DDM1.7) used to make tumor cell...

Platelet lysate as a serum replacement for skin cell culture on biomimetic PCL nanofibers.

Science.gov (United States)

Sovkova, Vera; Vocetkova, Karolina; Rampichova, Michala; Mickova, Andrea; Buzgo, Matej; Lukasova, Vera; Dankova, Jana; Filova, Eva; Necas, Alois; Amler, Evzen

2018-06-01

Platelets are a popular source of native growth factors for tissue engineering applications. The aim of the study was to verify the use of platelet lysate as a fetal bovine serum (FBS) replacement for skin cell culture. The cytokine content of the platelet lysate was characterized using the Bio-Plex system. The cells (fibroblasts, melanocytes, and keratinocytes) were cultured on PCL nanofibrous scaffolds to mimic their natural microenvironment. The cytokine content of the platelet lysate was determined, and to the cells, a medium containing platelet lysate or platelet lysate in combination with FBS was added. The results showed that 7% (v/v) platelet lysate was sufficient to supplement 10% (v/v) FBS in the culture of fibroblasts and keratinocytes. The combination of platelet lysate and FBS had a rather inhibitory effect on fibroblasts, in contrary to keratinocytes, where the effect was synergic. Platelet lysate did not sufficiently promote proliferation in melanocytes; however, the combination of FBS and platelet lysate yielded a better outcome and resulted in bipolar morphology of the cultured melanocytes. The data indicated that platelet lysate improved cell proliferation and metabolic activity and may be used as an additive to the cell culture media.

IMMUNITY STATE IN THE OFFSPRING OF RATS EXPOSED ANTIGENS TOXOPLASMA GONDII

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T. F. Sokolova

2014-01-01

Full Text Available Today the questions about possibility of development disturbances in the immune system of the fetus and the newborn in chronic toxoplasmosis are poorly understood. Aim of research: to detect immunological disturbances in the offspring of rats which have been administered antigens T. gondii.Two series of experiments was performed. In these experiments white female Wistar rats in the III trimester of pregnancy have been administered corpuscular antigen T. gondii. The 60 days-old offspring of these rats have been included in study group of 137 animals. CD3+ cells count was performed in peripherical blood and standard suspension of splenocytesrats offspring. Peripherical blood cells count was performed in the blood of the rats offspring. In the second experiment rats offspring have been administered sheep erythrocytes in 5 days, before euthanasia. In spleen of this rats antigen-produced cells was counted.In control group was included 118 animals, which was born from white female Wistar rats have been administered 0,9% NaCl solution. CD3+ cells was detected in Cytomics FC500 flow cytometry analyzer (Beckman Coulter,USA by use rats origne-specifed monoclonal antibodies Anti-Rat CD3-FITC (Beckman Coulter,USA. Hematological parameters was assessed by use hematological analyzer Excell-22 (USA.We observed, that CD3+ lymphocytes and antigen-produced cells was decreased in test group (degress of decrease CD3+ cells was 17,2%; р = 0,003 in spleen vs. control group, degress of decrease antigen-produced cells was 27,3%; р = 0,03 vs. control group. Number of leukocytes was increased in in test group (34,5%; р = 0,009 vs. control group. Power and strength correlation pleiades between studied blood and spenal markers were higher in in test group vs. control group (∑Gi = 16; ∑Di = 4,38 vs. ∑Gi = 13; ∑Di = 2,28. This phenomenon is probably due to the development adaptive reactions disruption in the immune system and development

Polyclonal antibodies for the detection of Trypanosoma cruzi circulating antigens.

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Edith S Málaga-Machaca

2017-11-01

Full Text Available Detection of Trypanosoma cruzi antigens in clinical samples is considered an important diagnostic tool for Chagas disease. The production and use of polyclonal antibodies may contribute to an increase in the sensitivity of immunodiagnosis of Chagas disease.Polyclonal antibodies were raised in alpacas, rabbits, and hens immunized with trypomastigote excreted-secreted antigen, membrane proteins, trypomastigote lysate antigen and recombinant 1F8 to produce polyclonal antibodies. Western blot analysis was performed to determine specificity of the developed antibodies. An antigen capture ELISA of circulating antigens in serum, plasma and urine samples was developed using IgY polyclonal antibodies against T. cruzi membrane antigens (capture antibody and IgG from alpaca raised against TESA. A total of 33 serum, 23 plasma and 9 urine samples were analyzed using the developed test. Among serum samples, compared to serology, the antigen capture ELISA tested positive in 55% of samples. All plasma samples from serology positive subjects were positive in the antigen capture ELISA. All urine positive samples had corresponding plasma samples that were also positive when tested by the antigen capture ELISA.Polyclonal antibodies are useful for detection of circulating antigens in both the plasma and urine of infected individuals. Detection of antigens is direct evidence of the presence of the parasite, and could be a better surrogate of current infection status.

Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens.

Science.gov (United States)

Ruedl, C; Frühwirth, M; Wick, G; Wolf, H

1994-03-01

We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens. After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G [IgG], IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence. The procedure followed the principle of the classical ELISPOT test with nitrocellulose-bottomed microtiter plates, but europium (Eu3+)-linked streptavidin rather than enzyme-conjugated streptavidin was used, with the advantage of quantifying secreted immunoglobulins instead of detecting single antibody-secreting cells. Lymphocytes isolated from the lungs of treated animals revealed significant increases in total and antigen-specific IgA synthesis compared with the rates of the controls, whereas IgG and IgM production rates showed no remarkable differences. In addition, the sera of treated mice revealed higher antigen-specific IgA titers but not increased IgM and IgG levels. We conclude that priming the gut-associated lymphoid tissue with bacterial antigens of pneumotropic microorganisms can elicit an enhanced IgA response in a distant mucosal effector site, such as the respiratory tract, according to the concept of a common mucosa-associated immune system.

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...

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

KAUST Repository

Reid, Adam James

2012-03-22

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

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.

Pregnancy and Toxoplasma Infection

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Cihan Cetin

2016-12-01

Full Text Available Toxoplasmosis is an infectious disease caused by a protozoa named Toxoplasma gondii. It is a very important disease because it is related to fetal anomalies and poor perinatal outcomes like abortus and stillbirth. It spreads via uncooked meat and contaminated food. Timely and appropriate treatment and management of this infection prenatally reduces the risk of serious neurological sequelae. Therefore it is crucial that clinician who takes care of pregnant women know this infection deeply. In this review we aimed to summarize the prenatal diagnosis, complications and treatment of toxoplasma infection. [Archives Medical Review Journal 2016; 25(4.000: 457-466

Effect of platelet lysate on human cells involved in different phases of wound healing.

Science.gov (United States)

Barsotti, Maria Chiara; Chiara Barsotti, Maria; Losi, Paola; Briganti, Enrica; Sanguinetti, Elena; Magera, Angela; Al Kayal, Tamer; Feriani, Roberto; Di Stefano, Rossella; Soldani, Giorgio

2013-01-01

Platelets are rich in mediators able to positively affect cell activity in wound healing. Aim of this study was to characterize the effect of different concentrations of human pooled allogeneic platelet lysate on human cells involved in the different phases of wound healing (inflammatory phase, angiogenesis, extracellular matrix secretion and epithelialization). Platelet lysate effect was studied on endothelial cells, monocytes, fibroblasts and keratinocytes, in terms of viability and proliferation, migration, angiogenesis, tissue repair pathway activation (ERK1/2) and inflammatory response evaluation (NFκB). Results were compared both with basal medium and with a positive control containing serum and growth factors. Platelet lysate induced viability and proliferation at the highest concentrations tested (10% and 20% v/v). Whereas both platelet lysate concentrations increased cell migration, only 20% platelet lysate was able to significantly promote angiogenic activity (pplatelet lysate concentrations activated important inflammatory pathways such as ERK1/2 and NFκB with the same early kinetics, whereas the effect was different for later time-points. These data suggest the possibility of using allogeneic platelet lysate as both an alternative to growth factors commonly used for cell culture and as a tool for clinical regenerative application for wound healing.

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 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 ...

Global Analysis of Palmitoylated Proteins in Toxoplasma gondii.

Science.gov (United States)

Foe, Ian T; Child, Matthew A; Majmudar, Jaimeen D; Krishnamurthy, Shruthi; van der Linden, Wouter A; Ward, Gary E; Martin, Brent R; Bogyo, Matthew

2015-10-14

Post-translational modifications (PTMs) such as palmitoylation are critical for the lytic cycle of the protozoan parasite Toxoplasma gondii. While palmitoylation is involved in invasion, motility, and cell morphology, the proteins that utilize this PTM remain largely unknown. Using a chemical proteomic approach, we report a comprehensive analysis of palmitoylated proteins in T. gondii, identifying a total of 282 proteins, including cytosolic, membrane-associated, and transmembrane proteins. From this large set of palmitoylated targets, we validate palmitoylation of proteins involved in motility (myosin light chain 1, myosin A), cell morphology (PhIL1), and host cell invasion (apical membrane antigen 1, AMA1). Further studies reveal that blocking AMA1 palmitoylation enhances the release of AMA1 and other invasion-related proteins from apical secretory organelles, suggesting a previously unrecognized role for AMA1. These findings suggest that palmitoylation is ubiquitous throughout the T. gondii proteome and reveal insights into the biology of this important human pathogen. Copyright © 2015 Elsevier Inc. All rights reserved.

Susceptibility of pregnant women to toxoplasma infection--potential benefits for newborn screening.

LENUS (Irish Health Repository)

Ferguson, W

2008-08-20

Congenital toxoplasmosis (CT) arises as a result of new acquisition of Toxoplasma infection by a susceptible woman during pregnancy. Early detection of CT through neonatal screening programmes could optimize management and improve infant outcome. This study sought to estimate the prevalence of Toxoplasma susceptibility in pregnant women. As detection of Toxoplasma antibodies in neonatal blood reflects maternal exposure history, maternal antibody seroprevalence was determined using anonymized residual blood from newborn screening cards. A total of 20,252 cards were tested in 1 year. 4,991 (24.6%) cards tested positive for Toxoplasma antibody. Results were stratified by county. Toxoplasma antibody seroprevalence rates of 25% indicated that Toxoplasma infection is common in Ireland and that up to 75% of women remain susceptible to primary infection during pregnancy. This study aimed to a) determine the seroprevalence of Toxoplasma antibody in pregnant women, and hence b) estimate the risk for acquisition of primary toxoplasmosis in pregnancy in order to support an application to fund a pilot newborn screening programme.

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.

TOXOPLASMA AND VIRAL ANTIBODIES AMONG HIV PATIENTS AND INMATES IN CENTRAL JAVA, INDONESIA.

Science.gov (United States)

Sari, Yulia; Haryati, Sri; Raharjo, Irvan; Prasetyo, Afiono Agung

2015-11-01

In Indonesia, Toxoplasma and its associations with blood-borne viruses have been poorly studied. In order to study the association between anti-Toxoplasma antibodies and blood-borne viral antibodies, blood samples from 497 participants (375 inmates from four prisons in Central Java, Indonesia and 122 HIV patients at a Voluntary Counseling and Testing Clinic in Surakarta, Indonesia) were tested for serological markers of Toxoplasma, human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and human T-lymphotropic virus types I and II (HTLV-1/2). Anti-Toxoplasma IgG and IgM positivity rates were 41.6% and 3.6%, respectively. One point two percent of participants was positive for both anti-Toxoplasma IgG and IgM antibodies. Sixteen point five percent, 11.3%, 2.6% and 2.8% of participants were positive for anti- Toxoplasma IgG combined with anti-HCV antibodies, anti-Toxoplasma IgG combined with anti-HIV antibodies, anti-Toxoplasma IgM combined with anti-HIV antibodes and anti-Toxoplasma IgG combined with both anti-HIV and anti-HCV antibodies, respectively. Anti-Toxoplasma IgM seropositivity was associated with anti-HIV (aOR = 4.3; 95% CI: 1.112-16.204, p = 0.034). Anti-Toxoplasma IgG antibodies were associated with anti-HCV (aOR = 2.8; 95% CI: 1.749-4.538, p < 0.001) and history of injection drug use (aOR = 3.1; 95% CI: 1.905-5.093, p < 0.001). In conclusion, we recommend patients with HIV, HCV infection and injection drug users should be screened for Toxoplasma infection in Indonesia.

Effect of platelet lysate on human cells involved in different phases of wound healing.

Directory of Open Access Journals (Sweden)

Maria Chiara Barsotti

Full Text Available BACKGROUND: Platelets are rich in mediators able to positively affect cell activity in wound healing. Aim of this study was to characterize the effect of different concentrations of human pooled allogeneic platelet lysate on human cells involved in the different phases of wound healing (inflammatory phase, angiogenesis, extracellular matrix secretion and epithelialization. METHODOLOGY/PRINCIPAL FINDINGS: Platelet lysate effect was studied on endothelial cells, monocytes, fibroblasts and keratinocytes, in terms of viability and proliferation, migration, angiogenesis, tissue repair pathway activation (ERK1/2 and inflammatory response evaluation (NFκB. Results were compared both with basal medium and with a positive control containing serum and growth factors. Platelet lysate induced viability and proliferation at the highest concentrations tested (10% and 20% v/v. Whereas both platelet lysate concentrations increased cell migration, only 20% platelet lysate was able to significantly promote angiogenic activity (p<0.05 vs. control, comparably to the positive control. Both platelet lysate concentrations activated important inflammatory pathways such as ERK1/2 and NFκB with the same early kinetics, whereas the effect was different for later time-points. CONCLUSION/SIGNIFICANCE: These data suggest the possibility of using allogeneic platelet lysate as both an alternative to growth factors commonly used for cell culture and as a tool for clinical regenerative application for wound healing.

An Extended Surface Loop on Toxoplasma gondii Apical Membrane Antigen 1 (AMA1 Governs Ligand Binding Selectivity.

Directory of Open Access Journals (Sweden)

Michelle L Parker

Full Text Available Apicomplexan parasites are the causative agents of globally prevalent diseases including malaria and toxoplasmosis. These obligate intracellular pathogens have evolved a sophisticated host cell invasion strategy that relies on a parasite-host cell junction anchored by interactions between apical membrane antigens (AMAs on the parasite surface and rhoptry neck 2 (RON2 proteins discharged from the parasite and embedded in the host cell membrane. Key to formation of the AMA1-RON2 complex is displacement of an extended surface loop on AMA1 called the DII loop. While conformational flexibility of the DII loop is required to expose the mature RON2 binding groove, a definitive role of this substructure has not been elucidated. To establish a role of the DII loop in Toxoplasma gondii AMA1, we engineered a form of the protein where the mobile portion of the loop was replaced with a short Gly-Ser linker (TgAMA1ΔDIIloop. Isothermal titration calorimetry measurements with a panel of RON2 peptides revealed an influential role for the DII loop in governing selectivity. Most notably, an Eimeria tenella RON2 (EtRON2 peptide that showed only weak binding to TgAMA1 bound with high affinity to TgAMA1ΔDIIloop. To define the molecular basis for the differential binding, we determined the crystal structure of TgAMA1ΔDIIloop in complex with the EtRON2 peptide. When analyzed in the context of existing AMA1-RON2 structures, spatially distinct anchor points in the AMA1 groove were identified that, when engaged, appear to provide the necessary traction to outcompete the DII loop. Collectively, these data support a model where the AMA1 DII loop serves as a structural gatekeeper to selectively filter out ligands otherwise capable of binding with high affinity in the AMA1 apical groove. These data also highlight the importance of considering the functional implications of the DII loop in the ongoing development of therapeutic intervention strategies targeting the AMA1-RON

Possible role of Toxoplasma gondii in brain cancer through modulation of host microRNAs

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Thirugnanam Sivasakthivel

2013-02-01

Full Text Available Abstract Background The obligate intracellular protozoan parasite Toxoplasma gondii infects humans and other warm-blooded animals and establishes a chronic infection in the central nervous system after invasion. Studies showing a positive correlation between anti-Toxoplasma antibodies and incidences of brain cancer have led to the notion that Toxoplasma infections increase the risk of brain cancer. However, molecular events involved in Toxoplasma induced brain cancers are not well understood. Presentation of the hypothesis Toxoplasma gains control of host cell functions including proliferation and apoptosis by channelizing parasite proteins into the cell cytoplasm and some of the proteins are targeted to the host nucleus. Recent studies have shown that Toxoplasma is capable of manipulating host micro RNAs (miRNAs, which play a central role in post-transcriptional regulation of gene expression. Therefore, we hypothesize that Toxoplasma promotes brain carcinogenesis by altering the host miRNAome using parasitic proteins and/or miRNAs. Testing the hypothesis The miRNA expression profiles of brain cancer specimens obtained from patients infected with Toxoplasma could be analyzed and compared with that of normal tissues as well as brain cancer tissues from Toxoplasma uninfected individuals to identify dysregulated miRNAs in Toxoplasma-driven brain cancer cells. Identified miRNAs will be further confirmed by studying cancer related miRNA profiles of the different types of brain cells before and after Toxoplasma infection using cell lines and experimental animals. Expected outcome The miRNAs specifically associated with brain cancers that are caused by Toxoplasma infection will be identified. Implications of the hypothesis Toxoplasma infection may promote initiation and progression of cancer by modifying the miRNAome in brain cells. If this hypothesis is true, the outcome of this research would lead to the development of novel biomarkers and

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

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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.

Enhanced specificity in immunoscreening of expression cDNA clones using radiolabeled antigen overlay

International Nuclear Information System (INIS)

Chao, S.; Chao, L.; Chao, J.

1989-01-01

A highly sensitive and specific method has been developed for immunoscreening clones from an expression cDNA library. The procedures utilize a radiolabeled antigen detection method described originally for the immunoblotting of plasma proteins. Screening of rat alpha 1-antitrypsin clones was used. Comparison between Western blots of alpha 1-antitrypsin using both labeled antigen and protein A detection methods showed that the former yielded lower background and greater sensitivity than the latter. Further, this technique was shown to have a lower detection limit of less than 20 ng through Western blot analysis of varying concentrations of alpha 1-antitrypsin. The procedures are based on the expression of the protein by cDNA clones containing the DNA inserts in the correct reading frame. Following the transfer of phage proteins to nitrocellulose membranes, the bivalent antibodies bind monovalently to both nitrocellulose-bound-antigen in the phage lysates and radiolabeled antigen. The radiolabeled antigen overlay method is superior to the protein A detection method in sensitivity, specificity and reproducibility. This improved method can be applied in general for screening expression cDNA libraries, provided that the specific antiserum and radiolabeled antigen are available

Production of refolded Toxoplasma gondii recombinant SAG1-related sequence 3 (SRS3) and its use for serodiagnosis of human toxoplasmosis.

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Mirzadeh, Abolfazl; Saadatnia, Geita; Golkar, Majid; Babaie, Jalal; Noordin, Rahmah

2017-05-01

SAG1-related sequence 3 (SRS3) is one of the major Toxoplasma gondii tachyzoite surface antigens and has been shown to be potentially useful for the detection of toxoplasmosis. This protein is highly conformational due to the presence of six disulfide bonds. To achieve solubility and antigenicity, SRS3 depends on proper disulfide bond formation. The aim of this study was to over-express the SRS3 protein with correct folding for use in serodiagnosis of the disease. To achieve this, a truncated SRS3 fusion protein (rtSRS3) was produced, containing six histidyl residues at both terminals and purified by immobilized metal affinity chromatography. The refolding process was performed through three methods, namely dialysis in the presence of chemical additives along with reduced/oxidized glutathione and drop-wise dilution methods with reduced/oxidized glutathione or reduced DTT/oxidized glutathione. Ellman's assay and ELISA showed that the protein folding obtained by the dialysis method was the most favorable, probably due to the correct folding. Subsequently, serum samples from individuals with chronic infection (n = 76), probable acute infection (n = 14), and healthy controls (n = 81) were used to determine the usefulness of the refolded rtSRS3 for Toxoplasma serodiagnosis. The results of the developed IgG-ELISA showed a diagnostic specificity of 91% and a sensitivity of 82.89% and 100% for chronic and acute serum samples, respectively. In conclusion, correctly folded rtSRS3 has the potential to be used as a soluble antigen for the detection of human toxoplasmosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Parasites and cancers: parasite antigens as possible targets for cancer immunotherapy.

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Darani, Hossein Yousofi; Yousefi, Morteza

2012-12-01

An adverse relationship between some parasite infections and cancer in the human population has been reported by different research groups. Anticancer activity of some parasites such as Trypanosoma cruzi, Toxoplasma gondii, Toxocara canis, Acantamoeba castellani and Plasmodium yoelii has been shown in experimental animals. Moreover, it has been shown that cancer-associated mucin-type O-glycan compositions are made by parasites, therefore cancers and parasites have common antigens. In this report anticancer activities of some parasites have been reviewed and the possible mechanisms of these actions have also been discussed.

The effect of platelet lysate supplementation of a dextran-based hydrogel on cartilage formation.

Science.gov (United States)

Moreira Teixeira, Liliana S; Leijten, Jeroen C H; Wennink, Jos W H; Chatterjea, Anindita G; Feijen, Jan; van Blitterswijk, Clemens A; Dijkstra, Pieter J; Karperien, Marcel

2012-05-01

In situ gelating dextran-tyramine (Dex-TA) injectable hydrogels have previously shown promising features for cartilage repair. Yet, despite suitable mechanical properties, this system lacks intrinsic biological signals. In contrast, platelet lysate-derived hydrogels are rich in growth factors and anti-inflammatory cytokines, but mechanically unstable. We hypothesized that the advantages of these systems may be combined in one hydrogel, which can be easily translated into clinical settings. Platelet lysate was successfully incorporated into Dex-TA polymer solution prior to gelation. After enzymatic crosslinking, rheological and morphological evaluations were performed. Subsequently, the effect of platelet lysate on cell migration, adhesion, proliferation and multi-lineage differentiation was determined. Finally, we evaluated the integration potential of this gel onto osteoarthritis-affected cartilage. The mechanical properties and covalent attachment of Dex-TA to cartilage tissue during in situ gel formation were successfully combined with the advantages of platelet lysate, revealing the potential of this enhanced hydrogel as a cell-free approach. The addition of platelet lysate did not affect the mechanical properties and porosity of Dex-TA hydrogels. Furthermore, platelet lysate derived anabolic growth factors promoted proliferation and triggered chondrogenic differentiation of mesenchymal stromal cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

Stimulation with lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae maximizes cross-reactivity of anti-fungal T cells.

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Deo, Shivashni S; Virassamy, Balaji; Halliday, Catriona; Clancy, Leighton; Chen, Sharon; Meyer, Wieland; Sorrell, Tania C; Gottlieb, David J

2016-01-01

Invasive fungal diseases caused by filamentous fungi and yeasts are significant causes of morbidity and mortality in immunosuppressed hematology patients. We previously published a method to expand Aspergillus fumigatus-specific T cells for clinical cell therapy. In the present study, we investigated expansion of T cells specific for other fungal pathogens and creation of a broadly reactive panfungal T-cell product. Fungal strains selected were those frequently observed in the clinical hematology setting and included Aspergillus, Candida, Fusarium, Rhizopus and Lomentospora/Scedosporium. Four T-cell cultures specific to each fungus were established. We selected lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae to expand panfungal T cells. Allelic restriction of anti-fungal activity was determined through the use of specific major histocompatibility complex class II-blocking antibodies. Individual T-cell cultures specific to each fungus could be expanded in vitro, generating predominantly CD4(+) T cells of which 8% to 20% were fungus-specific. We successfully expanded panfungal T cells from the peripheral blood (n = 8) and granulocyte-colony-stimulating factor-primed stem cell products (n = 3) of normal donors by using a combination of lysates from Aspergillus terreus, Candida krusei and Rhizopus oryzae. Anti-fungal activity was mediated through human leukocyte antigen (HLA)-DR alleles and was maintained when antigen-presenting cells from partially HLA-DRB1-matched donors were used to stimulate T cells. We demonstrate a method to manufacture panfungal T-cell products with specificity against a range of clinical fungal pathogens by use of the blood and stem cells of healthy donors as the starting material. The safety and efficacy of these products will need to be tested clinically. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Toxoplasma gondii Actively Inhibits Neuronal Function in Chronically Infected Mice

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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

Toxoplasma gondii actively inhibits neuronal function in chronically infected mice.

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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.

Toxoplasmosis (Toxoplasma infection) Treatment

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... Form Controls Cancel Submit Search the CDC Parasites - Toxoplasmosis (Toxoplasma infection) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Toxoplasmosis General Information Toxoplasmosis FAQs Toxoplasmosis & Pregnancy FAQs Epidemiology & ...

Cloning and expression of Toxoplasma gondii tachyzoite P22 protein

African Journals Online (AJOL)

Jane

2011-08-01

Aug 1, 2011 ... Expressd protein was purified by affinity chromatography and confirmed by western blot ... Key words: Toxoplasma gondii, cloning, recombinant P22. INTRODUCTION. Toxoplasma gondii ..... an ELISA Assay. Iran. J. Immunol.

Inflammasome sensor NLRP1 controls rat macrophage susceptibility to Toxoplasma gondii.

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Kimberly M Cirelli

2014-03-01

Full Text Available Toxoplasma gondii is an intracellular parasite that infects a wide range of warm-blooded species. Rats vary in their susceptibility to this parasite. The Toxo1 locus conferring Toxoplasma resistance in rats was previously mapped to a region of chromosome 10 containing Nlrp1. This gene encodes an inflammasome sensor controlling macrophage sensitivity to anthrax lethal toxin (LT induced rapid cell death (pyroptosis. We show here that rat strain differences in Toxoplasma infected macrophage sensitivity to pyroptosis, IL-1β/IL-18 processing, and inhibition of parasite proliferation are perfectly correlated with NLRP1 sequence, while inversely correlated with sensitivity to anthrax LT-induced cell death. Using recombinant inbred rats, SNP analyses and whole transcriptome gene expression studies, we narrowed the candidate genes for control of Toxoplasma-mediated rat macrophage pyroptosis to four genes, one of which was Nlrp1. Knockdown of Nlrp1 in pyroptosis-sensitive macrophages resulted in higher parasite replication and protection from cell death. Reciprocally, overexpression of the NLRP1 variant from Toxoplasma-sensitive macrophages in pyroptosis-resistant cells led to sensitization of these resistant macrophages. Our findings reveal Toxoplasma as a novel activator of the NLRP1 inflammasome in rat macrophages.

Optimizing parameters for clinical-scale production of high IL-12 secreting dendritic cells pulsed with oxidized whole tumor cell lysate

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Chiang Cheryl L-L

2011-11-01

Full Text Available Abstract Background Dendritic cells (DCs are the most potent antigen-presenting cell population for activating tumor-specific T cells. Due to the wide range of methods for generating DCs, there is no common protocol or defined set of criteria to validate the immunogenicity and function of DC vaccines. Methods Monocyte-derived DCs were generated during 4 days of culture with recombinant granulocyte-macrophage colony stimulating factor and interleukin-4, and pulsed with tumor lysate produced by hypochlorous acid oxidation of tumor cells. Different culture parameters for clinical-scale DC preparation were investigated, including: 1 culture media; 2 culture surface; 3 duration of activating DCs with lipopolysaccharide (LPS and interferon (IFN-gamma; 4 method of DC harvest; and 5 cryomedia and final DC product formulation. Results DCs cultured in CellGenix DC media containing 2% human AB serum expressed higher levels of maturation markers following lysate-loading and maturation compared to culturing with serum-free CellGenix DC media or AIM-V media, or 2% AB serum supplemented AIM-V media. Nunclon™Δ surface, but not Corning® tissue-culture treated surface and Corning® ultra-low attachment surface, were suitable for generating an optimal DC phenotype. Recombinant trypsin resulted in reduced major histocompatibility complex (MHC Class I and II expression on mature lysate-loaded DCs, however presentation of MHC Class I peptides by DCs was not impaired and cell viability was higher compared to cell scraping. Preservation of DCs with an infusible cryomedia containing Plasma-Lyte A, dextrose, sodium chloride injection, human serum albumin, and DMSO yielded higher cell viability compared to using human AB serum containing 10% DMSO. Finally, activating DCs for 16 hours with LPS and IFN-γ stimulated robust mixed leukocyte reactions (MLRs, and high IL-12p70 production in vitro that continued for 24 hours after the cryopreserved DCs were thawed and

Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells

International Nuclear Information System (INIS)

Hareyama, Masato

1988-01-01

We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-γ. In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G 2 /M phases of the cell cycle than in G 0 /G 1 . The expression of YH206 antigen was enhanced in the S and G 2 /M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens. (author)

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 ...

Platelet lysates produced from expired platelet concentrates support growth and osteogenic differentiation of mesenchymal stem cells.

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Sandra Mjoll Jonsdottir-Buch

Full Text Available BACKGROUND: Mesenchymal stem cells are promising candidates in regenerative cell therapy. Conventional culture methods involve the use of animal substances, specifically fetal bovine serum as growth supplement. Since the use of animal-derived products is undesirable for human applications, platelet lysates produced from human platelets are an attractive alternative. This is especially true if platelet lysates from already approved transfusion units at blood banks can be utilized. The purpose of this study was to produce human platelet lysates from expired, blood bank-approved platelet concentrates and evaluate their use as growth supplement in the culture of mesenchymal stem cells. METHODOLOGY/PRINCIPAL FINDINGS: In this study, bone marrow-derived mesenchymal stem cells were cultured with one of three culture supplements; fetal bovine serum, lysates from freshly prepared human platelet concentrates, or lysates from expired human platelet concentrates. The effects of these platelet-derived culture supplements on basic mesenchymal stem cell characteristics were evaluated. All cultures maintained the typical mesenchymal stem cell surface marker expression, trilineage differentiation potential, and the ability to suppress in vitro immune responses. However, mesenchymal stem cells supplemented with platelet lysates proliferated faster than traditionally cultured cells and increased the expression of the osteogenic marker gene RUNX-2; yet no difference between the use of fresh and expired platelet concentrates was observed. CONCLUSION/SIGNIFICANCE: Our findings suggest that human platelet lysates produced from expired platelet concentrates can be used as an alternative to fetal bovine serum for mesenchymal stem cell culture to the same extent as lysates from fresh platelets.

Morbillivirus and Toxoplasma exposure and association with hematological parameters for southern Beaufort Sea polar bears: potential response to infectious agents in a sentinel species

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Kirk, Cassandra M.; Amstrup, Steven C.; Swor, Rhonda; Holcomb, Darce; O'Hara, Todd M.

2010-01-01

Arctic temperatures are increasing in response to greenhouse gas forcing and polar bears have already responded to changing conditions. Declines in body stature and vital rates have been linked to warming-induced loss of sea-ice. As food webs change and human activities respond to a milder Arctic, exposure of polar bears and other arctic marine organisms to infectious agents may increase. Because of the polar bear’s status as arctic ecosystem sentinel, polar bear health could provide an index of changing pathogen occurrence throughout the Arctic, however, exposure and monitoring protocols have yet to be established. We examine prevalence of antibodies to Toxoplasma gondii, and four morbilliviruses (canine distemper [CDV], phocine distemper [PDV], dolphin morbillivirus [DMV], porpoise morbillivirus [PMV]) including risk factors for exposure. We also examine the relationships between antibody levels and hematologic values established in the previous companion article. Antibodies to Toxoplasma gondii and morbilliviruses were found in both sample years. We found a significant inverse relationship between CDV titer and total leukocytes, neutrophils, monocytes, and eosinophils, and a significant positive relationship between eosinophils and Toxoplasma gondii antibodies. Morbilliviral prevalence varied significantly among age cohorts, with 1–2 year olds least likely to be seropositive and bears aged 5–7 most likely. Data suggest that the presence of CDV and Toxoplasma gondii antibodies is associated with polar bear hematologic values. We conclude that exposure to CDV-like antigen is not randomly distributed among age classes and suggest that differing behaviors among life history stages may drive probability of specific antibody presence.

Morbillivirus and Toxoplasma exposure and association with hematological parameters for southern Beaufort Sea polar bears: potential response to infectious agents in a sentinel species.

Science.gov (United States)

Kirk, Cassandra M; Amstrup, Steven; Swor, Rhonda; Holcomb, Darce; O'Hara, Todd M

2010-09-01

Arctic temperatures are increasing in response to greenhouse gas forcing and polar bears have already responded to changing conditions. Declines in body stature and vital rates have been linked to warming-induced loss of sea-ice. As food webs change and human activities respond to a milder Arctic, exposure of polar bears and other arctic marine organisms to infectious agents may increase. Because of the polar bear's status as arctic ecosystem sentinel, polar bear health could provide an index of changing pathogen occurrence throughout the Arctic, however, exposure and monitoring protocols have yet to be established. We examine prevalence of antibodies to Toxoplasma gondii, and four morbilliviruses (canine distemper [CDV], phocine distemper [PDV], dolphin morbillivirus [DMV], porpoise morbillivirus [PMV]) including risk factors for exposure. We also examine the relationships between antibody levels and hematologic values established in the previous companion article. Antibodies to Toxoplasma gondii and morbilliviruses were found in both sample years. We found a significant inverse relationship between CDV titer and total leukocytes, neutrophils, monocytes, and eosinophils, and a significant positive relationship between eosinophils and Toxoplasma gondii antibodies. Morbilliviral prevalence varied significantly among age cohorts, with 1-2 year olds least likely to be seropositive and bears aged 5-7 most likely. Data suggest that the presence of CDV and Toxoplasma gondii antibodies is associated with polar bear hematologic values. We conclude that exposure to CDV-like antigen is not randomly distributed among age classes and suggest that differing behaviors among life history stages may drive probability of specific antibody presence.

Platelet lysate and chondroitin sulfate loaded contact lenses to heal corneal lesions.

Science.gov (United States)

Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Delfino, Alessio; Riva, Federica; Icaro Cornaglia, Antonia; Marrubini, Giorgio; Musitelli, Giorgio; Del Fante, Claudia; Perotti, Cesare; Caramella, Carla; Ferrari, Franca

2016-07-25

Hemoderivative tear substitutes contain various ephiteliotrophic factors, such as growth factors (GF), involved in ocular surface homeostasis without immunogenic properties. The aim of the present work was the loading of platelet lysate into contact lenses to improve the precorneal permanence of platelet lysate growth factors on the ocular surface to enhance the treatment of corneal lesions. To this purpose, chondroitin sulfate, a sulfated glycosaminoglycan, which is normally present in the extracellular matrix, was associated with platelet lysate. In fact, chondroitin sulfate is capable of electrostatic interaction with positively charged growth factors, in particular, with bFGF, IGF, VEGF, PDGF and TGF-β, resulting in their stabilization and reduced degradation in solution. In the present work, various types of commercially available contact lenses have been loaded with chondroitin sulfate or chondroitin sulfate in association with platelet lysate to achieve a release of growth factors directly onto the corneal surface lesions. One type of contact lenses (PureVision(®)) showed in vitro good proliferation properties towards corneal cells and were able to enhance cut closure in cornea constructs. Copyright © 2016 Elsevier B.V. All rights reserved.

Platelet lysate formulations based on mucoadhesive polymers for the treatment of corneal lesions.

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Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Ferrari, Franca; Mori, Michela; Del Fante, Claudia; Perotti, Cesare; Scudeller, Luigia; Caramella, Carla

2011-02-01

Growth factors contained in platelet α-granules initiate and modulate tissue repair and are proposed for the treatment of soft and hard-tissue surgical conditions and in the management of non-healing wounds. Platelet lysate is a hemoderivative obtained from platelet-rich plasma and is capable of releasing a pool of growth factors. Many medical and surgical techniques have been proposed for the treatment of corneal lesions; management of these conditions remains problematic and healing with standard protocols is unattainable. The aim of this study was to develop formulations suitable for prolonging the contact of platelet lysate with the damaged cornea for the time necessary to exert a therapeutic effect. Two vehicles, one based on polyacrylic acid and one based on chitosan, were autoclaved and loaded with platelet lysate and the resultant formulations were characterized for rheology, mucoadhesion, vehicle compatibility and stability. The proliferation effect was tested on two cell culture types (rabbit corneal epithelial cells and fibroblasts). An in-vitro wound-healing test was performed on fibroblasts. In both cases the formulations were compared with platelet lysate diluted with saline at the same concentration. Both formulations maintained the rheological and mucoadhesive properties of the vehicles and the proliferative activity of platelet lysate. The chitosan formulation was able to significantly enhance epithelial cell growth even after storage of up to 2 weeks (in-use conditions), while the polyacrylic acid formulation was less efficient, probably due to the characteristics of the cell model used. The in-vitro wound-healing test performed on fibroblasts confirmed the differences between the two vehicles. The effect induced by the platelet lysate and chitosan formulation was faster than that of the polyacrylic acid formulation and complete in-vitro wound repair was achieved within 48 h. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society.

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 ...

Comparative Effects of Platelet-Rich Plasma, Platelet Lysate, and Fetal Calf Serum on Mesenchymal Stem Cells.

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Lykov, A P; Bondarenko, N A; Surovtseva, M A; Kim, I I; Poveshchenko, O V; Pokushalov, E A; Konenkov, V I

2017-10-01

We studied the effects of human platelet-rich plasma and platelet lysate on proliferation, migration, and colony-forming properties of rat mesenchymal stem cells. Platelet-rich plasma and platelet lysate stimulated the proliferation, migration, and colony formation of mesenchymal stem cells. A real-time study showed that platelet-rich plasma produces the most potent stimulatory effect, while both platelet-rich plasma and platelet lysate stimulated migration of cells.

[Seroprevalance Differences of Toxoplasma Between Syrian Refugees Pregnants and Indigenous Turkish Pregnants in Kahramanmaraş].

Science.gov (United States)

Bakacak, Murat; Serin, Salih; Aral, Murat; Ercan, Önder; Köstü, Bülent; Kireçci, Ahmet; Bostancı, Mehmet Sühha; Bakacak, Zeyneb

2015-06-01

In this study, we aimed to compare the Syrian refugees and resident Turkish pregnant population in terms of Toxoplasma seroprevalence. Data acquired from Kahramanmaraş Necip Fazıl City Hospital Department of Obstetrics and Gynecology between 2012 and 2013 were analyzed retrospectively. Results of 7201 Toxoplasma IgM tests and 4113 Toxoplasma IgG tests were evaluated. For 2012 and 2013 Toxoplasma IgM seropositivity was found in Syrian refugees 4.76% and 4.84% respectively in our study. In the same population Toxoplasma IgG seropositivity rates were 80% and 62.6%, respectively. Toxoplasma IgM seropositivity rates for the native peoples in Turkey in 2012 and 2013 was 1.96% and 2.34%, while in the same population Toxoplasma IgG seropositivity was detected 49.7% and 45.7% respectively. Toxoplasma IgM seropositivity was statistically higher in Syrian refugees for each year (p Syrian refugees was statistically higher (p Syrian refugees living in the region of Kahramanmaraş were statistically higher than the rates of local inhabitants, we consider that this condition should be taken into account in the follow-ups of Syrian pregnant refugees outnumbering in Kahramanmaraş and its vicinity.

Toxoplasmosis (Toxoplasma infection) Disease Symptoms

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... Form Controls Cancel Submit Search the CDC Parasites - Toxoplasmosis (Toxoplasma infection) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Toxoplasmosis General Information Toxoplasmosis FAQs Toxoplasmosis & Pregnancy FAQs Epidemiology & ...

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

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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.

A novel method for radiolabeling antigen-binding receptors of lymphocytes

International Nuclear Information System (INIS)

Choi, Y.S.; Lee, M.S.; Rosenspire, A.J.

1983-01-01

Antigen-binding receptor (ABR) molecules have been selectively radiolabeled and isolated from immunized chicken spleen cells. The specific radiolabeling of the receptors has been accomplished by utilizing a novel technique employing lactoperoxidase (LPO) covalently linked to antigen (Ag) for which human gammaglobulin was used. The cell surface ABRs were first bound to the Ag-LPO conjugates through specific recognition sites on the Ag portion of the conjugates. The bound LPO portions were then allowed to catalyze the radioiodination of the ABRs. After radiolabeling, cells were solubilized with detergents, ABRs still bound to Ag-LPO conjugates were directly isolated from the lysates via immunoaffinity chromatography utilizing an immunoaffinity reagent directed toward the antigen portion of the ABR-Ag-LPO complex. The radioactive materials were then analyzed via SDS-PAGE under reducing conditions. Most of the specifically-labeled and isolated materials were immunoglobulin (Ig). Both the membrane-bound form of the heavy chain as well as the secreted form were detected, along with the light chain. An additional polypeptide was also selectively labeled and isolated along with the Ig. This may be a molecule closely associated with the membrane immunoglobulin on the B-cell surface. (author)

Discovery of native autoantigens via antigen surrogate technology: application to type 1 diabetes.

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Doran, Todd M; Simanski, Scott; Kodadek, Thomas

2015-02-20

A fundamental goal in understanding the mechanisms of autoimmune disease is the characterization of autoantigens that are targeted by autoreactive antibodies and T cells. Unfortunately, the identification of autoantigens is a difficult problem. We have begun to explore a novel route to the discovery of autoantibody/autoantigen pairs that involves comparative screening of combinatorial libraries of unnatural, synthetic molecules for compounds that bind antibodies present at much higher levels in the serum of individuals with a given autoimmune disease than in the serum of control individuals. We have shown that this approach can yield "antigen surrogates" capable of capturing disease-specific autoantibodies from serum. In this report, we demonstrate that the synthetic antigen surrogates can be used to affinity purify the autoantibodies from serum and that these antibodies can then be used to identify their cognate autoantigen in an appropriate tissue lysate. Specifically, we report the discovery of a peptoid able to bind autoantibodies present in about one-third of nonobese diabetic (NOD) mice. The peptoid-binding autoantibodies were highly enriched through peptoid affinity chromatography and employed to probe mouse pancreatic and brain lysates. This resulted in identification of murine GAD65 as the native autoantigen. GAD65 is a known humoral autoantigen in human type 1 diabetes mellitus (T1DM), but its existence in mice had been controversial. This study demonstrates the potential of this chemical approach for the unbiased identification of autoantigen/autoantibody complexes.

Immunization of C57BL/6 Mice with GRA2 Combined with MPL Conferred Partial Immune Protection against Toxoplasma gondii

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Babaie, Jalal; Amiri, Samira; Homayoun, Robab; Azimi, Ebrahim; Mohabati, Reyhaneh; Berizi, Mahboobe; Sadaie, M. Reza; Golkar, Majid

2018-01-01

We have previously reported that immunization with GRA2 antigen of Toxoplasma gondii induces protective immunity in CBA/J (H2k) and BALB/c mice (H2d). We aimed to examine whether immunization of a distinct strain of rodent with recombinant dense granule antigens (GRA2) combined with monophosphorryl lipid A (MPL) adjuvant elicits protective immune response against T. gondii. C57BL/6 (H2b haplotype) mice were immunized with GRA2, formulated in MPL adjuvant. Strong humoral response, predominantly of IgG1 subclass and cellular response, IFN-γ, was detected at three weeks post immunization. Mice immunized with GRA2 had significantly (p < 0.01) fewer brain cysts than those in the adjuvant group, upon challenge infection. Despite the production of a strong antibody response, IFN-γ production and brain cyst reduction were not significant when the immunized mice were infected four months after the immunization. We can conclude that GRA2 immunization partially protects against T. gondii infection in C57BL/6 mice, though the potency and longevity of this antigen as a standalone vaccine may vary in distinct genetic backgrounds. This observation further emphasizes the utility of GRA2 for incorporation into a multi-antigenic vaccine against T. gondii.

Limited Value of Assays Using Detection of Immunoglobulin G Antibodies to the Two Recombinant Dense Granule Antigens, GRA1 and GRA6 Nt of Toxoplasma gondii, for Distinguishing between Acute and Chronic Infections in Pregnant Women

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Ferrandiz, Josette; Mercier, Corinne; Wallon, Martine; Picot, Stéphane; Cesbron-Delauw, Marie-France; Peyron, François

2004-01-01

An enzyme-linked immunosorbent assay (ELISA) using two recombinant antigens of Toxoplasma gondii (GRA1 and GRA6 Nt) was developed in order to differentiate between pregnant women with a serological profile of recently acquired infection and those with chronic infection. Both proteins were expressed in Escherichia coli as glutathione S-transferase fusion proteins. Thirty-two serum samples from subjects who presented seroconversion within 3 months before sampling (group 1; acute profile), 46 serum samples from women who had a positive serology at least 1 year before sampling (group 2; chronic profile), and 100 serum samples from pregnant women who were not infected by T. gondii (group 3) were examined for immunoglobulin G (IgG) reactivity. For both antigens, the specificity reached 98%. In both groups of infected patients, the overall sensitivity scored was 60% for GRA1 and 83% for GRA6 Nt. In group 1, 34% of sera reacted with GRA1 whereas 84% of sera reacted with GRA6 Nt; in group 2, however, sensitivities were 78.2 and 82.6%, respectively. Combination of the readings obtained with both antigens yielded a sensitivity of 91%. A serological follow-up of 10 women who seroconverted during pregnancy displayed three different serological patterns: (i) a GRA profile paralleling the IgG curve, as detected by the commercial kit, (ii) a GRA1 profile, or (iii) GRA1 and GRA6 Nt profiles remaining negative for at least 8 weeks after the reference test gave positive results. Taken together, these results suggest that neither GRA1 nor GRA6 Nt is sensitive enough to be used routinely to differentiate between acute and chronic toxoplasmic infections. PMID:15539499

Cloning and expression of Toxoplasma gondii tachyzoite P22 protein

African Journals Online (AJOL)

Delay in diagnosis of Toxoplasma gondii infection in pregnant women who have been infected during the first trimester of gestation can lead to death of her fetus. Serological tests based on recombinant proteins are the main diagnosis methods for the detection of anti Toxoplasma antibody in serum samples. The aim of this ...

Producción de anticuerpos policlonales IgG contra una proteína con actividad de óxido nítrico sintetasa de Toxoplasma gondii recombinante (NOS-Tg-r y marcación inmunológica en taquizoítoso Production of Polyclonal Antibodies against Toxoplasma gondii Recombinant protein with Nitric Oxide Synthase activity and immunologic marking in Tachyzoites

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Jonathan Mauricio Padilla-Londoño

2008-06-01

adjuvant: aluminum hydroxide and Freund ’s adjuvant. We tested the generation of polyclonal antibodies by an indirect ELISA assay. The results showed that levels of antibodies were higher in rabbits immunized with Freund ’s adjuvant than with aluminum hydroxide (p =0.005. In order to test cross reactions, we used a recombinant Toxoplasma metallooprotease, a recombinant cysteine protease from Entamoeba histolytica, albumin 2%, hydroxide aluminium and Freund ’s adjuvant as antigens on indirect ELISA assays for the polyclonal serum antibodies. No serum showed absorbances higher than the cutoff level with these antigens, indicating that the polyclonal antibodies were specific for recombinant Toxoplasma NOS. Additionally, we performed immunodetection of the enzyme on Toxoplasma gondii tachyzoites and we obtained a diffuse labeling of the parasite.

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

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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.

Toxoplasma gondii infection specifically increases the levels of key host microRNAs.

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Gusti M Zeiner

2010-01-01

Full Text Available The apicomplexan parasite Toxoplasma gondii can infect and replicate in virtually any nucleated cell in many species of warm-blooded animals; thus, it has evolved the ability to exploit well-conserved biological processes common to its diverse hosts. Here we have investigated whether Toxoplasma modulates the levels of host microRNAs (miRNAs during infection.Using microarray profiling and a combination of conventional molecular approaches we report that Toxoplasma specifically modulates the expression of important host microRNAs during infection. We show that both the primary transcripts for miR-17 approximately 92 and miR-106b approximately 25 and the pivotal miRNAs that are derived from miR-17 approximately 92 display increased abundance in Toxoplasma-infected primary human cells; a Toxoplasma-dependent up-regulation of the miR-17 approximately 92 promoter is at least partly responsible for this increase. The abundance of mature miR-17 family members, which are derived from these two miRNA clusters, remains unchanged in host cells infected with the closely related apicomplexan Neospora caninum; thus, the Toxoplasma-induced increase in their abundance is a highly directed process rather than a general host response to infection.Altered levels of miR-17 approximately 92 and miR-106b approximately 25 are known to play crucial roles in mammalian cell regulation and have been implicated in numerous hyperproliferative diseases although the mechanisms driving their altered expression are unknown. Hence, in addition to the implications of these findings on the host-pathogen interaction, Toxoplasma may represent a powerful probe for understanding the normal mechanisms that regulate the levels of key host miRNAs.

Purification-Free, Target-Selective Immobilization of a Protein from Cell Lysates.

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Cha, Jaehyun; Kwon, Inchan

2018-02-27

Protein immobilization has been widely used for laboratory experiments and industrial processes. Preparation of a recombinant protein for immobilization usually requires laborious and expensive purification steps. Here, a novel purification-free, target-selective immobilization technique of a protein from cell lysates is reported. Purification steps are skipped by immobilizing a target protein containing a clickable non-natural amino acid (p-azidophenylalanine) in cell lysates onto alkyne-functionalized solid supports via bioorthogonal azide-alkyne cycloaddition. In order to achieve a target protein-selective immobilization, p-azidophenylalanine was introduced into an exogenous target protein, but not into endogenous non-target proteins using host cells with amber codon-free genomic DNAs. Immobilization of superfolder fluorescent protein (sfGFP) from cell lysates is as efficient as that of the purified sfGFP. Using two fluorescent proteins (sfGFP and mCherry), the authors also demonstrated that the target proteins are immobilized with a minimal immobilization of non-target proteins (target-selective immobilization). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Predator cat odors activate sexual arousal pathways in brains of Toxoplasma gondii infected rats.

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Patrick K House

Full Text Available Cat odors induce rapid, innate and stereotyped defensive behaviors in rats at first exposure, a presumed response to the evolutionary pressures of predation. Bizarrely, rats infected with the brain parasite Toxoplasma gondii approach the cat odors they typically avoid. Since the protozoan Toxoplasma requires the cat to sexually reproduce, this change in host behavior is thought to be a remarkable example of a parasite manipulating a mammalian host for its own benefit. Toxoplasma does not influence host response to non-feline predator odor nor does it alter behavior on olfactory, social, fear or anxiety tests, arguing for specific manipulation in the processing of cat odor. We report that Toxoplasma infection alters neural activity in limbic brain areas necessary for innate defensive behavior in response to cat odor. Moreover, Toxoplasma increases activity in nearby limbic regions of sexual attraction when the rat is exposed to cat urine, compelling evidence that Toxoplasma overwhelms the innate fear response by causing, in its stead, a type of sexual attraction to the normally aversive cat odor.

Predator cat odors activate sexual arousal pathways in brains of Toxoplasma gondii infected rats.

Science.gov (United States)

House, Patrick K; Vyas, Ajai; Sapolsky, Robert

2011-01-01

Cat odors induce rapid, innate and stereotyped defensive behaviors in rats at first exposure, a presumed response to the evolutionary pressures of predation. Bizarrely, rats infected with the brain parasite Toxoplasma gondii approach the cat odors they typically avoid. Since the protozoan Toxoplasma requires the cat to sexually reproduce, this change in host behavior is thought to be a remarkable example of a parasite manipulating a mammalian host for its own benefit. Toxoplasma does not influence host response to non-feline predator odor nor does it alter behavior on olfactory, social, fear or anxiety tests, arguing for specific manipulation in the processing of cat odor. We report that Toxoplasma infection alters neural activity in limbic brain areas necessary for innate defensive behavior in response to cat odor. Moreover, Toxoplasma increases activity in nearby limbic regions of sexual attraction when the rat is exposed to cat urine, compelling evidence that Toxoplasma overwhelms the innate fear response by causing, in its stead, a type of sexual attraction to the normally aversive cat odor.

The transcriptome of Toxoplasma gondii

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Roos David S

2005-12-01

Full Text Available Abstract Background Toxoplasma gondii gives rise to toxoplasmosis, among the most prevalent parasitic diseases of animals and man. Transformation of the tachzyoite stage into the latent bradyzoite-cyst form underlies chronic disease and leads to a lifetime risk of recrudescence in individuals whose immune system becomes compromised. Given the importance of tissue cyst formation, there has been intensive focus on the development of methods to study bradyzoite differentiation, although the molecular basis for the developmental switch is still largely unknown. Results We have used serial analysis of gene expression (SAGE to define the Toxoplasma gondii transcriptome of the intermediate-host life cycle that leads to the formation of the bradyzoite/tissue cyst. A broad view of gene expression is provided by >4-fold coverage from nine distinct libraries (~300,000 SAGE tags representing key developmental transitions in primary parasite populations and in laboratory strains representing the three canonical genotypes. SAGE tags, and their corresponding mRNAs, were analyzed with respect to abundance, uniqueness, and antisense/sense polarity and chromosome distribution and developmental specificity. Conclusion This study demonstrates that phenotypic transitions during parasite development were marked by unique stage-specific mRNAs that accounted for 18% of the total SAGE tags and varied from 1–5% of the tags in each developmental stage. We have also found that Toxoplasma mRNA pools have a unique parasite-specific composition with 1 in 5 transcripts encoding Apicomplexa-specific genes functioning in parasite invasion and transmission. Developmentally co-regulated genes were dispersed across all Toxoplasma chromosomes, as were tags representing each abundance class, and a variety of biochemical pathways indicating that trans-acting mechanisms likely control gene expression in this parasite. We observed distinct similarities in the specificity and

Human platelet lysate as a promising growth-stimulating additive for culturing of stem cells and other cell types.

Science.gov (United States)

Shanskii, Ya D; Sergeeva, N S; Sviridova, I K; Kirakozov, M S; Kirsanova, V A; Akhmedova, S A; Antokhin, A I; Chissov, V I

2013-11-01

We compared the composition and biological activity of fetal calf serum and platelet lysate from donor platelet concentrate. In platelet lysate, the concentrations of alkaline phosphatase, lactate dehydrogenase, creatinine, and mineral metabolism parameters were lower, while parameters of lipid and protein metabolism were higher than in fetal calf serum. The concentrations of growth factors (platelet-derived (AA, AB, BB), vascular endothelial, insulin-like, and transforming growth factor β) in platelet lysate 1.7-148.7-fold surpassed the corresponding parameters in fetal calf serum. After replacement of fetal calf serum with platelet lysate in the culture medium (0, 25, 50, 75, and 100%), the count of multipotent mesenchymal stromal cells on day 7 (in comparison with day 1) increased by 154.8, 206.6, 228.2, 367.7, and 396.5%, respectively. Thus, platelet lysate can be an adequate non-xenogenic alternative for fetal calf serum.

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.

The effect of lysate of spleen cells after low dose radiation (LDR) on NK activity

International Nuclear Information System (INIS)

Lu Duicai; Su Liaoyuan

2003-01-01

To find effect of lysate of spleen cells after LDR on NK activity of CD 57 cells or non-CD 57 cells, lysate of spleen cells after LDR were extracted. McAb (anti CD 57 cells) was used to separate CD 57 cells from human peripheral blood by Panning direct method. The CD 57 cells and non-CD 57 cells were used as effective cells. K 562 cells labelled by 3 H-TdR were used as target cells. The ratio of effect cells to target cells was 10:1. NK activity of CD 57 cells or non-CD 5 -7 cells with the lysate of spleen cells after LDR was reflected by the efficiency of anti tumor cells. The 3 H-TdR incorporation in K 562 cells cultured with non-CD 57 cells was significantly lower than that with CD 57 cells. After use of the lysate of spleen cells after LDR, NK activities of CD 57 cells and non-CD 57 cells were 1.24 and 1.58 respectively. They were both increased obviously compared with control groups. The effect of anti K 562 cells of non-CD 57 cells is even greater than that of CD 57 cells. The lysate of spleen cells after LDR can enhance the effect of both non-CD 57 cells and CD 57 cells

Seroprevalensi Toxoplasma gondii pada Kambing dan Bioassay Patogenitasnya pada Kucing

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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;}

Effect of Different Adjuvants on Protection and Side-Effects Induced by Helicobacter suis Whole-Cell Lysate Vaccination.

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Iris Bosschem

Full Text Available Helicobacter suis (H. suis is a widespread porcine gastric pathogen, which is also of zoonotic importance. The first goal of this study was to investigate the efficacy of several vaccine adjuvants (CpG-DNA, Curdlan, Freund's Complete and Incomplete, Cholera toxin, administered either subcutaneously or intranasally along with H. suis whole-cell lysate, to protect against subsequent H. suis challenge in a BALB/c infection model. Subcutaneous immunization with Freund's complete (FC/lysate and intranasal immunization with Cholera toxin (CT/lysate were shown to be the best options for vaccination against H. suis, as determined by the amount of colonizing H. suis bacteria in the stomach, although adverse effects such as post-immunization gastritis/pseudo-pyloric metaplasia and increased mortality were observed, respectively. Therefore, we decided to test alternative strategies, including sublingual vaccine administration, to reduce the unwanted side-effects. A CCR4 antagonist that transiently inhibits the migration of regulatory T cells was also included as a new adjuvant in this second study. Results confirmed that immunization with CT (intranasally or sublingually is among the most effective vaccination protocols, but increased mortality was still observed. In the groups immunized subcutaneously with FC/lysate and CCR4 antagonist/lysate, a significant protection was observed. Compared to the FC/lysate immunized group, gastric pseudo-pyloric metaplasia was less severe or even absent in the CCR4 antagonist/lysate immunized group. In general, an inverse correlation was observed between IFN-γ, IL-4, IL-17, KC, MIP-2 and LIX mRNA expression and H. suis colonization density, whereas lower IL-10 expression levels were observed in partially protected animals.

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

Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells. Immunological study using monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Hareyama, Masato

1988-12-01

We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-..gamma... In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G/sub 2//M phases of the cell cycle than in G/sub 0//G/sub 1/. The expression of YH206 antigen was enhanced in the S and G/sub 2//M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens.

Translational Control in Plasmodium and Toxoplasma Parasites

Science.gov (United States)

Joyce, Bradley R.; Sullivan, William J.; Nussenzweig, Victor

2013-01-01

The life cycles of apicomplexan parasites such as Plasmodium spp. and Toxoplasma gondii are complex, consisting of proliferative and latent stages within multiple hosts. Dramatic transformations take place during the cycles, and they demand precise control of gene expression at all levels, including translation. This review focuses on the mechanisms that regulate translational control in Plasmodium and Toxoplasma, with a particular emphasis on the phosphorylation of the α subunit of eukaryotic translation initiation factor 2 (eIF2α). Phosphorylation of eIF2α (eIF2α∼P) is a conserved mechanism that eukaryotic cells use to repress global protein synthesis while enhancing gene-specific translation of a subset of mRNAs. Elevated levels of eIF2α∼P have been observed during latent stages in both Toxoplasma and Plasmodium, indicating that translational control plays a role in maintaining dormancy. Parasite-specific eIF2α kinases and phosphatases are also required for proper developmental transitions and adaptation to cellular stresses encountered during the life cycle. Identification of small-molecule inhibitors of apicomplexan eIF2α kinases may selectively interfere with parasite translational control and lead to the development of new therapies to treat malaria and toxoplasmosis. PMID:23243065

Translational control in Plasmodium and toxoplasma parasites.

Science.gov (United States)

Zhang, Min; Joyce, Bradley R; Sullivan, William J; Nussenzweig, Victor

2013-02-01

The life cycles of apicomplexan parasites such as Plasmodium spp. and Toxoplasma gondii are complex, consisting of proliferative and latent stages within multiple hosts. Dramatic transformations take place during the cycles, and they demand precise control of gene expression at all levels, including translation. This review focuses on the mechanisms that regulate translational control in Plasmodium and Toxoplasma, with a particular emphasis on the phosphorylation of the α subunit of eukaryotic translation initiation factor 2 (eIF2α). Phosphorylation of eIF2α (eIF2α∼P) is a conserved mechanism that eukaryotic cells use to repress global protein synthesis while enhancing gene-specific translation of a subset of mRNAs. Elevated levels of eIF2α∼P have been observed during latent stages in both Toxoplasma and Plasmodium, indicating that translational control plays a role in maintaining dormancy. Parasite-specific eIF2α kinases and phosphatases are also required for proper developmental transitions and adaptation to cellular stresses encountered during the life cycle. Identification of small-molecule inhibitors of apicomplexan eIF2α kinases may selectively interfere with parasite translational control and lead to the development of new therapies to treat malaria and toxoplasmosis.

Expression cloning of camelid nanobodies specific for Xenopus embryonic antigens.

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Keiji Itoh

Full Text Available Developmental biology relies heavily on the use of conventional antibodies, but their production and maintenance involves significant effort. Here we use an expression cloning approach to identify variable regions of llama single domain antibodies (known as nanobodies, which recognize specific embryonic antigens. A nanobody cDNA library was prepared from lymphocytes of a llama immunized with Xenopus embryo lysates. Pools of bacterially expressed cDNAs were sib-selected for the ability to produce specific staining patterns in gastrula embryos. Three different nanobodies were isolated: NbP1 and NbP3 stained yolk granules, while the reactivity of NbP7 was predominantly restricted to the cytoplasm and the cortex. The isolated nanobodies recognized specific protein bands in immunoblot analysis. A reverse proteomic approach identified NbP1 target antigen as EP45/Seryp, a serine protease inhibitor. Given the unique stability of nanobodies and the ease of their expression in diverse systems, we propose that nanobody cDNA libraries represent a promising resource for molecular markers for developmental biology.

Heparin-associated thrombocytopenia: antibody binding specificity to platelet antigens.

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Lynch, D M; Howe, S E

1985-11-01

Sera from four patients with heparin-associated thrombocytopenia (HAT) were evaluated by a quantitative enzyme-linked immunosorbent assay (ELISA) to detect heparin-dependent serum platelet-bindable immunoglobulin (S-PBIg) and by Western blotting and immunoprecipitation to investigate the specificity of the antibody binding. All HAT sera showed mildly increased S-PBIg (mean, 7.8 fg per platelet; normal, less than 6.0 fg per platelet) to intact target platelets in the ELISA, which was markedly increased in the presence of heparin (mean, 20.9 fg per platelet). This increase was 20-fold greater than normal control sera, which showed a mean differential increase of only 0.5 fg per platelet. Immunoglobulin binding specificity to platelet antigens was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of platelet lysate with transfer of the platelet fractions onto nitrocellulose strips (Western blotting) and subsequent immunoassay using HAT and normal sera. In the presence of heparin, the four HAT patients demonstrated increased binding of immunoglobulin to platelet antigens of apparent molecular weights of 180, 124, and 82 kd. Radiolabeled heparin when incubated with HAT sera, normal sera, or albumin blanks bound to platelet proteins of the same apparent molecular weights. These observations are consistent with current hypotheses suggesting that HAT antibody is directed to heparin-platelet complexes or, alternatively, that heparin induces conformational change of antigenic sites on the platelet membrane.

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

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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.

Lactobacillus rhamnosus GG Lysate Increases Re-Epithelialization of Keratinocyte Scratch Assays by Promoting Migration.

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Mohammedsaeed, Walaa; Cruickshank, Sheena; McBain, Andrew J; O'Neill, Catherine A

2015-11-05

A limited number of studies have investigated the potential of probiotics to promote wound healing in the digestive tract. The aim of the current investigation was to determine whether probiotic bacteria or their extracts could be beneficial in cutaneous wound healing. A keratinocyte monolayer scratch assay was used to assess re-epithelialization; which comprises keratinocyte proliferation and migration. Primary human keratinocyte monolayers were scratched then exposed to lysates of Lactobacillus (L) rhamnosus GG, L. reuteri, L. plantarum or L. fermentum. Re-epithelialization of treated monolayers was compared to that of untreated controls. Lysates of L. rhamnosus GG and L. reuteri significantly increased the rate of re-epithelialization, with L. rhamnosus GG being the most efficacious. L. reuteri increased keratinocyte proliferation while L. rhamnosus GG lysate significantly increased proliferation and migration. Microarray analysis of L. rhamnosus GG treated scratches showed increased expression of multiple genes including the chemokine CXCL2 and its receptor CXCR2. These are involved in normal wound healing where they stimulate keratinocyte proliferation and/or migration. Increased protein expression of both CXCL2 and CXCR2 were confirmed by ELISA and immunoblotting. These data demonstrate that L. rhamnosus GG lysate accelerates re-epithelialization of keratinocyte scratch assays, potentially via chemokine receptor pairs that induce keratinocyte migration.

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

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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.

Optimizing Production of Antigens and Fabs in the Context of Generating Recombinant Antibodies to Human Proteins.

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Nan Zhong

Full Text Available We developed and optimized a high-throughput project workflow to generate renewable recombinant antibodies to human proteins involved in epigenetic signalling. Three different strategies to produce phage display compatible protein antigens in bacterial systems were compared, and we found that in vivo biotinylation through the use of an Avi tag was the most productive method. Phage display selections were performed on 265 in vivo biotinylated antigen domains. High-affinity Fabs (<20nM were obtained for 196. We constructed and optimized a new expression vector to produce in vivo biotinylated Fabs in E. coli. This increased average yields up to 10-fold, with an average yield of 4 mg/L. For 118 antigens, we identified Fabs that could immunoprecipitate their full-length endogenous targets from mammalian cell lysates. One Fab for each antigen was converted to a recombinant IgG and produced in mammalian cells, with an average yield of 15 mg/L. In summary, we have optimized each step of the pipeline to produce recombinant antibodies, significantly increasing both efficiency and yield, and also showed that these Fabs and IgGs can be generally useful for chromatin immunoprecipitation (ChIP protocols.

Antiretroviral activity of protease inhibitors against Toxoplasma gondii

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Lianet Monzote

2013-02-01

Full Text Available The introduction of highly active antiretroviral therapy (HAART has caused a marked reduction in the occurrence and severity of parasitic infections, including the toxoplasmic encephalitis (TE. These changes have been attributed to the restoration of cell-mediated immunity. This study was developed to examine the activity of six antiretroviral protease inhibitors (API on Toxoplasma gondii tachyzoites. The six API showed anti-Toxoplasma activity, with IC50 value between 1.4 and 6.6 µg/mL. Further studies at the molecular level should be performed to clarify if the use of API could be beneficial or not for AIDS patients with TE.

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)

Toxoplasma-safe meat: close to reality?

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Kijlstra, A.; Jongert, E.

2009-01-01

In 2008, the centennial of the discovery of Toxoplasma gondii was celebrated. However, toxoplasmosis is still seen as a neglected and underreported disease, despite having a disease burden similar to that of salmonellosis and campylobacteriosis. Human vaccines are not available and current

Feasibility and Efficiency of Human Bone Marrow Stromal Cell Culture with Allogeneic Platelet Lysate-Supplementation for Cell Therapy against Stroke

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Chengbo Tan

2016-01-01

Full Text Available Currently, there is increasing interest in human bone marrow stromal cells (hBMSCs as regeneration therapy against cerebral stroke. The aim of the present study was to evaluate the feasibility and validity of hBMSC cultures with allogeneic platelet lysates (PLs. Platelet concentrates (PC were harvested from healthy volunteers and made into single donor-derived PL (sPL. The PL mixtures (mPL were made from three different sPL. Some growth factors and platelet cell surface antigens were detected by enzyme-linked immunosorbent assay (ELISA. The hBMSCs cultured with 10% PL were analyzed for their proliferative potential, surface markers, and karyotypes. The cells were incubated with superparamagnetic iron oxide (SPIO agents and injected into a pig brain. MRI and histological analysis were performed. Consequently, nine lots of sPL and three mPL were prepared. ELISA analysis showed that PL contained adequate growth factors and a particle of platelet surface antigens. Cell proliferation capacity of PLs was equivalent to or higher than that of fetal calf serum (FCS. No contradiction in cell surface markers and no chromosomal aberrations were found. The MRI detected the distribution of SPIO-labeled hBMSCs in the pig brain. In summary, the hBMSCs cultured with allogeneic PL are suitable for cell therapy against stroke.

Platelet lysate obtained via plateletpheresis performed in standing and awake equine donors.

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Sumner, Scarlett M; Naskou, Maria C; Thoresen, Merrilee; Copland, Ian; Peroni, John F

2017-07-01

Platelet preparations containing growth factors, attachment factors, and enzymes are appealing to enhance healing of injured tissues and as an alternative to xenogenic serum in cell culture media. Plateletpheresis is commonly used to collect platelets in human medicine but has not been validated in horses. Plateletpheresis to collect platelet concentrate was performed on six female, mixed breed, chemically restrained horses using commercially available apheresis equipment. Before and immediately after plateletpheresis, we performed physical examinations and collected blood for chemistry and coagulation panels and then again at 8, 16, 24, and 48 hours after the procedure. To produce platelet lysate, the platelet concentrate underwent two freeze-thaw cycles followed by centrifugation and filtration processing. The platelet lysate was then analyzed for cellular debris, fibrinogen, and growth factors. The collected platelet concentration contained a mean platelet yield of 390 × 10 3 /μL. Donor platelet count decreased from a mean of 193 × 10 3 /μL to 138 × 10 3 /μL after plateletpheresis, but no individual was at risk for hemorrhage. Pooled platelet lysate had minimal cellular residue and contained growth factor concentrations at 6.1 ng/mL for transforming growth factor-β1, at 3.5 ng/mL for platelet-derived growth factor-BB, and at 13.8 ng/mL for vascular endothelial growth factor-A. Plateletpheresis using commercially available apheresis equipment is a feasible option for collecting platelet concentrate from equine donors. The lysate generated from the apheresis product contains growth factors and has potential to be used as a fetal bovine serum substitute for cell culture. © 2017 AABB.

Toxoplasma gondii and schizophrenia

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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; ...

Phenotype of dendritic cells generated in the presence of non-small cell lung cancer antigens - preliminary report.

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Dariusz Sagan

2009-01-01

Full Text Available Therapeutic outcomes of definitively treated non-small-cell lung cancer (NSCLC are unacceptably poor. It has been proposed that the manipulation of dendritic cells (DCs as a "natural" vaccine adjuvant may prove to be a particularly effective way to stimulate antitumor immunity. Presently, there is no standardized methodology for preparing vaccines and many questions concerning the optimal source and type of antigens as well as maturation state and activity of DCs are still unsolved. The study population comprised of ten patients with histologically confirmed NSCLC (mean age: 67.63 +/- 6.15 years. Resected small tumor pieces were placed in tissue culture dishes containing different growth factors in order to obtain pure cancer cells. Seven days after the operation, the PBMC were collected and monocytes were purified by the adherence to culture dishes. Monocytes were cultured in RPMI 1640 medium supplemented with 10% of autologous plasma in the presence of rhIL-4 and rhGM-CSF to generate immature autologous (DCs. TNF-alpha with or without tumor cells' lysate were added to maturation of DCs. After 7 days of culture, DCs were harvested and the expression of CD1a, CD83, CD80, CD86 and HLA-DR antigens were analyzed by flow cytometry. We discovered higher (p=0.07 percentage of semimature DCs in tumor cell lysate culture in comparison with TNF-alpha culture (21.22 +/- 16.82% versus 11.27 +/- 11.64%. The expression of co-stimulatory and maturation markers (CD86, CD83 and HLA-DR was higher on DCs from the culture with tumor cell lysate compared with TNF-alpha culture as a control. Specimen of NSCLC's culture prepared in this way could generate differences in DCs phenotype, which may have an influence on the therapeutic and protective antitumor immunity of the vaccine. Our research seems to be the next step in the development of DC-based vaccine. We are going to continue the investigation to start the preparation of a pattern of immunological vaccine

Toxoplasma gondii infection in workers occupationally exposed to unwashed raw fruits and vegetables: a case control seroprevalence study

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Alvarado-Esquivel Cosme

2011-12-01

Full Text Available Abstract Background Through a case control seroprevalence study, we sought to determine the association of Toxoplasma gondii infection with occupational exposure to unwashed raw fruits and vegetables. Methods Subjects, numbering 200, who worked growing or selling fruits and vegetables, and 400 control subjects matched by age, gender, and residence were examined by enzyme immunoassays for the presence of anti-Toxoplasma IgG and IgM antibodies. Socio-demographic, clinical, and behavioral characteristics from the study subjects were obtained. Results Of the 200 fruit and vegetable workers, 15 (7.5% of whom, and 31 (7.8% of the 400 controls were positive for anti-Toxoplasma IgG antibodies (P = 0.96. Anti-Toxoplasma IgM antibodies were found in 2 (1% of the fruit workers and in 11 (2.8% of the control subjects (P = 0.23. Seroprevalence of Toxoplasma antibodies increased with age (P = 0.0004. In addition, seropositivity to Toxoplasma was associated with ill status (P = 0.04, chronic tonsillitis (P = 0.03, and reflex impairment (P = 0.03. Multivariate analysis showed that Toxoplasma infection was associated with consumption of raw meat (OR = 5.77; 95% CI: 1.15-28.79; P = 0.03, unwashed raw fruits (OR = 2.50; 95% CI: 1.11-5.63; P = 0.02, and living in a house with soil floors (OR = 3.10; 95% CI: 1.22-7.88; P = 0.01, whereas Toxoplasma infection was negatively associated with traveling abroad (OR = 0.28; 95% CI: 0.12-0.67; P = 0.005. Conclusions This is the first report of seroprevalence and contributing factors for Toxoplasma infection in workers occupationally exposed to unwashed raw fruits and vegetables, and the results may help in the design of optimal preventive measures against Toxoplasma infection especially in female workers at reproductive age.

Risk factors for Toxoplasma gondii infection in Kohat District, Pakistan

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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.

Presence of anti-Toxoplasma antibodies in humans and their cats in the urban zone of Guadalajara

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Galván Ramírez María de la Luz

1999-01-01

Full Text Available Cats are the definitive hosts of Toxoplasma gondii. Infected cats excrete oocysts in their feces, infecting humans and other animals. The objective of the present study was to determine the presence of anti-Toxoplasma antibodies in cat owners and their pets, and determine if there was a relationship between Toxoplasma infection and humans who live with infected cats. IgG anti-Toxoplasma antibodies in sera of 59 cat owners were determined by enzyme-linked immunosorbent assay (ELISA, in 24 sera from their cats, IgG, IgM, and IgA antibodies were found using Burney's ELISA. Thirty-eight (64% of 59 cat owners were positive to IgG anti-Toxoplasma. Seropositivity for cats was 70.8% IgG, 8.3% IgM, and 62.5% IgA. Cohabitation with cats infected by T. gondii, feeding with leftovers or raw viscera, and lack of control over how their feces were handled are risk factors conducive for humans to become infected by T. gondii.

Fierce competition between Toxoplasma and Chlamydia for host cell structures in dually infected cells.

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Romano, Julia D; de Beaumont, Catherine; Carrasco, Jose A; Ehrenman, Karen; Bavoil, Patrik M; Coppens, Isabelle

2013-02-01

The prokaryote Chlamydia trachomatis and the protozoan Toxoplasma gondii, two obligate intracellular pathogens of humans, have evolved a similar modus operandi to colonize their host cell and salvage nutrients from organelles. In order to gain fundamental knowledge on the pathogenicity of these microorganisms, we have established a cell culture model whereby single fibroblasts are coinfected by C. trachomatis and T. gondii. We previously reported that the two pathogens compete for the same nutrient pools in coinfected cells and that Toxoplasma holds a significant competitive advantage over Chlamydia. Here we have expanded our coinfection studies by examining the respective abilities of Chlamydia and Toxoplasma to co-opt the host cytoskeleton and recruit organelles. We demonstrate that the two pathogen-containing vacuoles migrate independently to the host perinuclear region and rearrange the host microtubular network around each vacuole. However, Toxoplasma outcompetes Chlamydia to the host microtubule-organizing center to the detriment of the bacterium, which then shifts to a stress-induced persistent state. Solely in cells preinfected with Chlamydia, the centrosomes become associated with the chlamydial inclusion, while the Toxoplasma parasitophorous vacuole displays growth defects. Both pathogens fragment the host Golgi apparatus and recruit Golgi elements to retrieve sphingolipids. This study demonstrates that the productive infection by both Chlamydia and Toxoplasma depends on the capability of each pathogen to successfully adhere to a finely tuned developmental program that aims to remodel the host cell for the pathogen's benefit. In particular, this investigation emphasizes the essentiality of host organelle interception by intravacuolar pathogens to facilitate access to nutrients.

Drug Repurposing Screening Identifies Novel Compounds That Effectively Inhibit Toxoplasma gondii Growth

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Dittmar, Ashley J.; Drozda, Allison A.

2016-01-01

ABSTRACT The urgent need to develop new antimicrobial therapies has spawned the development of repurposing screens in which well-studied drugs and other types of compounds are tested for potential off-label uses. As a proof-of-principle screen to identify compounds effective against Toxoplasma gondii, we screened a collection of 1,120 compounds for the ability to significantly reduce Toxoplasma replication. A total of 94 compounds blocked parasite replication with 50% inhibitory concentrations of parasite invasion and replication but did so independently of inhibition of dopamine or other neurotransmitter receptor signaling. Tamoxifen, which is an established inhibitor of the estrogen receptor, also reduced parasite invasion and replication. Even though Toxoplasma can activate the estrogen receptor, tamoxifen inhibits parasite growth independently of this transcription factor. Tamoxifen is also a potent inducer of autophagy, and we find that the drug stimulates recruitment of the autophagy marker light chain 3-green fluorescent protein onto the membrane of the vacuolar compartment in which the parasite resides and replicates. In contrast to other antiparasitic drugs, including pimozide, tamoxifen treatment of infected cells leads to a time-dependent elimination of intracellular parasites. Taken together, these data suggest that tamoxifen restricts Toxoplasma growth by inducing xenophagy or autophagic destruction of this obligate intracellular parasite. IMPORTANCE There is an urgent need to develop new therapies to treat microbial infections, and the repurposing of well-characterized compounds is emerging as one approach to achieving this goal. Using the protozoan parasite Toxoplasma gondii, we screened a library of 1,120 compounds and identified several compounds with significant antiparasitic activities. Among these were pimozide and tamoxifen, which are well-characterized drugs prescribed to treat patients with psychiatric disorders and breast cancer

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

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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.

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal.

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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

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Selma Samiko Miyazaki Onuma

2014-12-01

Full Text Available Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are related apicomplexan parasites that cause reproductive and neurological disorders in a wide range of domestic and wild animals. In the present study, the immunofluorescence antibody test (IFAT was used to investigate the presence of antibodies against T. gondii, N. caninum and S. neurona in the sera of 11 free-living jaguars (Panthera onca in two protected areas in the Pantanal region of Mato Grosso state, Brazil. Ten jaguars (90.9% showed seropositivity for T. gondii, eight (72.7% for S. neurona, and seven (63.6% for N. caninum antigens. Our findings reveal exposure of jaguars to these related coccidian parasites and circulation of these pathogens in this wild ecosystem. To the best of our knowledge, this is the first serological detection of N. caninum and S. neurona in free-living jaguars.

Platelet lysate-based pro-angiogenic nanocoatings.

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Oliveira, Sara M; Pirraco, Rogério P; Marques, Alexandra P; Santo, Vítor E; Gomes, Manuela E; Reis, Rui L; Mano, João F

2016-03-01

Human platelet lysate (PL) is a cost-effective and human source of autologous multiple and potent pro-angiogenic factors, such as vascular endothelial growth factor A (VEGF A), fibroblast growth factor b (FGF b) and angiopoietin-1. Nanocoatings previously characterized were prepared by layer-by-layer assembling incorporating PL with marine-origin polysaccharides and were shown to activate human umbilical vein endothelial cells (HUVECs). Within 20 h of incubation, the more sulfated coatings induced the HUVECS to the form tube-like structures accompanied by an increased expression of angiogenic-associated genes, such as angiopoietin-1 and VEGF A. This may be a cost-effective approach to modify 2D/3D constructs to instruct angiogenic cells towards the formation of neo-vascularization, driven by multiple and synergistic stimulations from the PL combined with sulfated polysaccharides. The presence, or fast induction, of a stable and mature vasculature inside 3D constructs is crucial for new tissue formation and its viability. This has been one of the major tissue engineering challenges, limiting the dimensions of efficient tissue constructs. Many approaches based on cells, growth factors, 3D bioprinting and channel incorporation have been proposed. Herein, we explored a versatile technique, layer-by-layer assembling in combination with platelet lysate (PL), that is a cost-effective source of many potent pro-angiogenic proteins and growth factors. Results suggest that the combination of PL with sulfated polyelectrolytes might be used to introduce interfaces onto 2D/3D constructs with potential to induce the formation of cell-based tubular structures. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Early diagnosis of congenital toxoplasmosis in newborn infants using IgG subclasses against two Toxoplasma gondii recombinant proteins

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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.

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

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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.

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...

Prevalence of agglutinating antibodies to Toxoplasma gondii and Sarcocystis neurona in beavers (Castor canadensis) from Massachusetts

Science.gov (United States)

Jordan, C.N.; Kaur, T.; Koenen, K.; DeStefano, S.; Zajac, A.M.; Lindsay, D.S.

2005-01-01

The present study examined the seroprevalence of Toxoplasma gondii and Sarcocystls neurona in a population of beavers (Castor canadensis) from Massachusetts. Sixty-two blood samples were collected during the field seasons over 3 consecutive years from different animals. Blood was collected onto filter paper and shipped to the Department of Biomedical Sciences, Virginia Tech, Blacksburg, Virginia, for parasite testing. The samples were tested at dilutions of 1:25, 1:50, and 1:100 against each parasite antigen by modified agglutination tests to determine whether antibodies to either parasite were present in the blood. Six of 62 samples (10%) were positive for T. gondii, with 2 samples having titers of 1:25 and 4 having titers of 1:50. Four of 62 samples (6%) were positive for S. neurona, with 2 samples having titers of 1:25 and 2 having titers of 1:50. ?? American Society of Pathologists 2005.

USE OF BACTERIAL LYSATES IN COMPLEX TREATMENT OF RHINOSINUSITIDIS

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E.A. Vishneva

2011-01-01

Full Text Available Rhinosinusitis is a common term that means inflammation of the mucosa of paranasal and nasal cavities. In the last 10 years there was a three-fold increase in rhinosinusitis’ morbidity rates and annual increase of hospital admissions on the average of 1,5–2%. The prevalence of various forms of rhinosinusitidis among adult population is 5 to 15% and 5% among children. Such ubiquitous spreading is one of the leading factors that stipulate socio-economic burden of the disease. According to various studies, rhinosinusitidis dramatically decrease quality of life: these patients show more inferior results in tests upon pain sensitivity and social activity in comparison with patients with coronary heart disease and COPD; in approximately 26% of patients rhinosinusitidis are followed by development or progression of depression. Rhinosinusitis treatment is one of the hottest issues in modern otorhinolaryngology, that demand more financial support with every year. Achievments in immunology have become grounds for immunocorrection as part of complex treatment of such patients. Bacterial lysates are used as preventive medications.Key words: rhinosinusitidis, immunomodulators, bacterial lysates. (Voprosy sovremennoi pediatrii — Current Pediatrics. — 2011; 10 (6: 157–161

Characterization of immunogenic proteins of Cysticercus tenuicollis of goats

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A. Goswami

2013-10-01

Full Text Available Aim: To identify immunodominant proteins of cystic fluid antigens and whole cyst lysate antigens of Cysticercus tenuicollis, the larval stage of the canine tapeworm Taenia hydatigena. Materials and Methods: Three numbers of cysts of C. tenuicollis were collected from the mesentry of small intestine of goats after slaughter. C. tenuicollis cysts of each sample were washed thoroughly with PBS (pH 7.4. Two types of antigens i.e. cystic fluid antigens and whole cyst lysate antigens were prepared from each sample. Polypeptide profiles of cystic fluid antigens and whole cyst lysate antigens preparations of C. tunicollis were analysed by Sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE containing 10% gel. C. tenuicollis proteins resolved by SDS-PAGE were electrophoretically transferred from the gel to a nitrocellulose membrane and probed by western blotting using natural immune sera obtained from infected goats. C. tenuicollis proteins that were resolved by SDS-PAGE and reactive by immune sera of goat was estimated by a Soft ware programme named KODAK 1D Image Analysis Software. Results: A total of eight major polypeptides of molecular weight (Mr 149.4 kDa, 92.9 kDa, 74.2 kDa, 63.5 kDa, 36.2 kDa, 23.9 kDa, 15.7 kDa and 9.6 kDa were resolved by SDS-PAGE with minor variations. Out of these, three polypeptides of Mr 36.2 kDa, 23.9 kDa and 9.6 kDa were recognized as immunodominant polypeptides after western blotting. Both cystic fluid antigens and whole cyst lysate antigens resolved same Mr polypeptides by SDS-PAGE and identified same immunodominant polypeptides after western blotting. The immunodominant polipeptides of Mr 23.9 kDa and 9.6 kDa identified for the first time from both cystic fluid antigens and whole cyst lysate antigens prepared from Cysticercus tenuicollis. Conclusion: Eight polypeptides were resolved from cystic fluid antigens and whole cyst lysate antigens of Cysticercus tenuicollis by SDS-PAGe of which polypeptides of

Analysis of Reparative Activity of Platelet Lysate: Effect on Cell Monolayer Recovery In Vitro and Skin Wound Healing In Vivo.

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Sergeeva, N S; Shanskii, Ya D; Sviridova, I K; Karalkin, P A; Kirsanova, V A; Akhmedova, S A; Kaprin, A D

2016-11-01

Platelet lysate prepared from donor platelet concentrate and pooled according to a developed technique stimulates migration of multipotent mesenchymal stromal cells of the human adipose tissue and promotes healing of the monolayer defect in cultures of human fibroblasts and multipotent mesenchymal stromal cells in vitro in concentrations close those of fetal calf serum (5-10%). Lysate of platelets from platelet-rich rat blood plasma stimulated healing of the skin defect by promoting epithelialization and granulation tissue formation. The regenerative properties of platelet lysate in vivo increased with increasing its concentration.

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

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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.

Toxoplasma gondii in women with bad obstetric history and infertility: a five-year study

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Abida Malik

2014-02-01

Full Text Available Objective: To evaluate the role of Toxoplasma gondii in women with bad obstetric (BOH history and in women with primary and secondary infertility. Methods: This study was conducted in the Department of Microbiology, Jawaharlal Nehru Medical College and Hospital for a period of 5 years from January 2004 to December 2009. Quantitative determination of IgM antibodies to Toxoplasma gondii infection was done by IgM capture ELISA in patients with history of BOH or infertility. Results: Out of a total of 441 subjects included in the study, 417 (94.6% had a BOH and 24 (5.4% subjects had infertility. Toxoplasma was found to be more common in females with two or more abortions 52 (76.5%. Similarly in patients with infertility due to Toxoplasma, secondary infertility (66.7% was more common than primary infertility. About 40.3% patients with BOH and 20% patients with infertility had healthy live issues after treatment with spiramycin. Conclusions: Toxoplasmosis is thus, an easily treatable cause of abortions and infertility. All antenatal females and females with infertility should be screened for toxoplasmosis.

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....

Lymphocyte proliferation to mycobacterial antigens is detectable across a spectrum of HIV-associated tuberculosis

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Bakari Muhammad

2009-02-01

Full Text Available Abstract Background Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA in HIV-infected subjects with latent or active TB. Methods HIV-infected subjects with bacille Calmette Guérin (BCG scars and CD4 counts ≥ 200 cells/mm3 entering a TB booster vaccine trial in Tanzania had baseline in vivo and in vitro immune tests performed: tuberculin skin tests (TST, LPA and five day assays of interferon gamma (IFN-γ release. Assay antigens were early secreted antigenic target 6 (ESAT-6, antigen 85 (Ag85, and Mycobacterium tuberculosis whole cell lysate (WCL. Subjects were screened for active TB at enrollment by history, exam, sputum smear and culture. We compared antimycobacterial immune responses between subjects with and without latent or active TB at enrollment. Results Among 1885 subjects screened, 635 had latent TB and 13 had active TB. Subjects with latent TB were more likely than subjects without TB to have LPA responses to ESAT-6 (13.2% vs. 5.5%, P Conclusion Lymphoproliferative responses to mycobacteria are detectable during HIV-associated active TB, and are less sensitive but more specific than TST. Trial registration ClinicalTrials.gov Identifier NCT00052195.

Assessment of bone healing ability of calcium phosphate cements loaded with platelet lysate in rat calvarial defects.

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Babo, Pedro S; Carvalho, Pedro P; Santo, Vítor E; Faria, Susana; Gomes, Manuela E; Reis, Rui L

2016-11-01

Injectable calcium phosphate cements have been used as a valid alternative to autologous bone grafts for bone augmentation with the additional advantage of enabling minimally invasive implantation procedures and for perfectly fitting the tissue defect. Nevertheless, they have low biodegradability and lack adequate biochemical signaling to promote bone healing and remodeling. In previous in vitro studies, we observed that the incorporation of platelet lysate directly into the cement paste or loaded in hyaluronic acid microspheres allowed to modulate the cement degradation and the in vitro expression of osteogenic markers in seeded human adipose derived stem cells. The present study aimed at investigating the possible effect of this system in new bone formation when implanted in calvarial bilateral defects in rats. Different formulations were assessed, namely plain calcium phosphate cements, calcium phosphate cements loaded with human platelet lysate, hybrid injectable formulations composed of the calcium phosphate cement incorporating hyaluronin acid non-loaded microparticles (20% hyaluronin acid) or with particles loaded with platelet lysate. The degradability and new bone regrowth were evaluated in terms of mineral volume in the defect, measured by micro-computed tomography and histomorphometric analysis upon 4, 8 and 12 weeks of implantation. We observed that the incorporation of hyaluronin acid microspheres induced an overly rapid cement degradation, impairing the osteoconductive properties of the cement composites. Moreover, the incorporation of platelet lysate induced higher bone healing than the materials without platelet lysate, up to four weeks after surgery. Nevertheless, this effect was not found to be significant when compared to the one observed in the sham-treated group. © The Author(s) 2016.

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

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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.

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

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Dangoudoubiyam, S; Oliveira, J B; Víquez, C; Gómez-García, A; González, O; Romero, J J; Kwok, O C H; Dubey, J P; Howe, D K

2011-06-01

Serum samples from 315 horses from Costa Rica, Central America, were examined for the presence of antibodies against Sarcocystis neurona, Neospora spp., and Toxoplasma gondii by using the surface antigen (SAG) SnSAG2 enzyme-linked immunosorbent assay (ELISA), the NhSAG1 ELISA, and the modified agglutination test, respectively. Anti- S. neurona antibodies were found in 42.2% of the horses by using the SnSAG2 ELISA. Anti- Neospora spp. antibodies were found in only 3.5% of the horses by using the NhSAG1 ELISA, and only 1 of these horses was confirmed seropositive by Western blot. Antibodies to T. gondii were found in 34.0% of the horses tested, which is higher than in previous reports from North and South America. The finding of anti- S. neurona antibodies in horses from geographical areas where Didelphis marsupialis has wide distribution suggests that D. marsupialis is a potential definitive host for this parasite and a source of infection for these horses.

Seroprevalence of Toxoplasma gondii infection among patients with non-schizophrenic neurodevelopmental disorders in Alexandria, Egypt.

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Shehata, Amany I; Hassanein, Faika I; Abdul-Ghani, Rashad

2016-02-01

Toxoplasma gondii is an opportunistic parasite with neurotropic characteristics that can mediate neurodevelopmental disorders, including mental, behavioral and personality aspects of their hosts. Therefore, the seroprevalence of anti-Toxoplasma antibodies has been studied in patients with different neurological disorders from different localities. On searching online databases, however, we could not find published studies on the seroprevalence of anti-Toxoplasma antibodies among patients with neurodevelopmental disorders in Egypt. Therefore, the present preliminary study was conducted to determine the serological profile of T. gondii infection among patients with non-schizophrenic neurodevelopmental disorders in Alexandria, Egypt. Data and blood samples were collected from 188 patients recruited for the study from four mental rehabilitation centers in the period from July 2014 to March 2015. The overall seropositivity rates of IgM and IgG among patients were 16.5% (31/188) and 50.0% (94/188), respectively. Of the studied patients' characteristics, only age was significantly associated with anti-Toxoplasma IgG seropositivity, with older patients being about twice more likely exposed to infection. However, no statistically significant association was found with IgM. In addition, seropositivity of anti-Toxoplasma IgG, but not IgM, was significantly associated with non-schizophrenic neurodevelopmental disorders; however, neither IgG nor IgM showed a significant association with cognitive impairment as indicated by the intelligence quotient scores. Copyright © 2015 Elsevier B.V. All rights reserved.

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 ...

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 ...

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

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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.

Seroprevalance Anti-Toxoplasma gondii antibodies in children and adolescents with tourette syndrome/chronic motor or vocal tic disorder: A case-control study.

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Akaltun, İsmail; Kara, Tayfun; Sertan Kara, Soner; Ayaydın, Hamza

2018-05-01

Toxoplasma gondii infection may be associated with psychiatric disorders due to its neurological effects. The purpose of this study was to investigate the relation between tic disorders in children and adolescents and Anti-Toxoplasma IgG. 43 children diagnosed with Tourette's syndrome(TS) and 87 with chronic motor or vocal tic disorder(CMVTD), and 130 healthy volunteers, all aged 7-18, were enrolled. Anti-Toxoplasma IgG antibody levels obtained from blood specimens were investigated. Toxoplasma IgG positivity was determined in 16(37.2%) of the patients with TS, in 27(31%) of those with CMVTD and in 12(9.2%) members of the control group. Anti-Toxoplasma gondii antibody positivity was 5.827-fold higher in subjects with TS and 4.425-fold higher in subjects with CMVTD compared to the control group. Correlation was determined between a diagnosis of TS or CMVTD and Anti-Toxoplasma gondii antibodies. We think that it will be useful for the neuropsychiatric process associated with Anti-Toxoplasma gondii antibodies to be clarified. Copyright © 2018 Elsevier B.V. All rights reserved.

Aspects of Toxoplasma Infection on the Reproductive System of Experimentally Infected Rams (Ovis Aries

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Welber Daniel Zanetti Lopes

2009-01-01

Full Text Available Eight reproductive rams with no prior reproductive disease were distributed into three groups of infection with T. gondii: GI, 3 rams, 2.0×105 P strain oocysts; GII, 3 rams, 1.0×106 RH strain tachyzoites; GIII, 2 control rams. Clinical parameters were measured and serological evaluations (IIF were performed. Presence of the parasite in the semen was investigated by PCR and bioassay techniques. The rams presented clinical alterations (hyperthermia and apathy related to toxoplasmosis in both groups infected with Toxoplasma gondii. All the inoculated rams responded to antigenic stimulus, producing antibodies against T. gondii from postinoculation day 5 onwards. In ovine groups I and II, the greatest titers observed were 1 : 4096 and 1 : 8192, respectively. In semen samples collected from these two groups, the presence of T. gondii was detected by bioassay and PCR. This coccidian was isolated (bioassay and PCR in tissue pools (testicles, epididymis, seminal vesicle, and prostrate from two rams infected presenting oocysts and in one presenting tachyzoites.

Prevalence of encysted Toxoplasma gondii in raptors from Alabama.

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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.

Confocal microscope is able to detect calcium metabolic in neuronal infection by toxoplasma gondii

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Sensusiati, A. D.; Priya, T. K. S.; Dachlan, Y. P.

2017-05-01

Calcium metabolism plays a very important role in neurons infected by Toxoplasma. Detection of change of calcium metabolism of neuron infected by Toxoplasma and Toxoplasma requires the calculation both quantitative and qualitative method. Confocal microscope has the ability to capture the wave of the fluorescent emission of the fluorescent dyes used in the measurement of cell calcium. The purpose of this study was to prove the difference in calcium changes between infected and uninfected neurons using confocal microscopy. Neuronal culture of human-skin-derived neural stem cell were divided into 6 groups, consisting 3 uninfected groups and 3 infected groups. Among the 3 groups were 2 hours, 24 hours and 48 hours. The neuron Toxoplasma gondii ratio was 1:5. Observation of intracellular calcium of neuron and tachyzoite, evidence of necrosis, apoptosis and the expression of Hsp 70 of neuron were examined by confocal microscope. The normality of the data was analysed by Kolmogorov-Smirnov Test, differentiation test was checked by t2 Test, and ANOVAs, for correlation test was done by Pearson Correlation Test. The calcium intensity of cytosolic neuron and T. gondii was significantly different from control groups (pneurons both in quantitatively and qualitatively.

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

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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.

The neurotropic parasite Toxoplasma gondii increases dopamine metabolism

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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...

Determination of Antibodies (IgG, IgM against Toxoplasma gondii in Patients with Cancer

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M Pedram

2007-08-01

Full Text Available Background: The aim of this study was determination of antibodies (IgG, IgM against Toxoplasma in malignant patients in order to refer the patients on time to the physician for treatment.Methods: This study was carried out on 252 malignant patients and 252 healthy normal subjects (as control obtained from Shafa Hospital and Medical Diagnostic Laboratory (Iran-Zamin, in Ahwaz city. Patient's information was recorded in a questionnaire before sampling. Serum samples of patients were examined for IgG and IgM antibodies by ELISA technique using Trinity kits. Results: The results of this study revealed the presence of Toxoplasma antibodies in 114 (45.2% cases of patients who were positive for Toxoplasma IgG antibodies, and 26 (10.3% cases were confirmed to be positive for Toxoplasma IgM antibodies and also 17 (6.7% of cases had both IgG and IgM antibodies against Toxoplasma gondii. In control group 92 (36.5% cases and 15 (6% cases revealed seropositive for IgG and IgM antibodies, respectively. There were no significant differences between sex, close contact with cat, living region, chemotherapy, and seropositivity rate of toxoplasmosis in patients. Comparing the age groups, the highest seropositive rate showed in the age of 51 years or higher, and their rates had tendency to increase with age in both groups. No seropositivity significant relationship was found between patients and control group.Conclusion: According to the prevalence of positive cases in these patients, it is necessary to examine the patients for toxoplasmosis before, during and after chemotherapy.

Intranasal Coadministration of the Cry1Ac Protoxin with Amoebal Lysates Increases Protection against Naegleria fowleri Meningoencephalitis

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Rojas-Hernández, Saúl; Rodríguez-Monroy, Marco A.; López-Revilla, Rubén; Reséndiz-Albor, Aldo A.; Moreno-Fierros, Leticia

2004-01-01

Cry1Ac protoxin has potent mucosal and systemic adjuvant effects on antibody responses to proteins or polysaccharides. In this work, we examined whether Cry1Ac increased protective immunity against fatal Naegleria fowleri infection in mice, which resembles human primary amoebic meningoencephalitis. Higher immunoglobulin G (IgG) than IgA anti-N. fowleri responses were elicited in the serum and tracheopulmonary fluids of mice immunized by the intranasal or intraperitoneal route with N. fowleri lysates either alone or with Cry1Ac or cholera toxin. Superior protection against a lethal challenge with 5 × 104 live N. fowleri trophozoites was achieved for immunization by the intranasal route. Intranasal immunization of N. fowleri lysates coadministered with Cry1Ac increased survival to 100%; interestingly, immunization with Cry1Ac alone conferred similar protection to that achieved with amoebal lysates alone (60%). When mice intranasally immunized with Cry1Ac plus lysates were challenged with amoebae, both IgG and IgA mucosal responses were rapidly increased, but only the increased IgG response persisted until day 60 in surviving mice. The brief rise in the level of specific mucosal IgA does not exclude the role that this isotype may play in the early defense against this parasite, since higher IgA responses were detected in nasal fluids of mice intranasally immunized with lysates plus either Cry1Ac or cholera toxin, which, indeed, were the treatments that provided the major protection levels. In contrast, serum antibody responses do not seem to be related to the protection level achieved. Both acquired and innate immune systems seem to play a role in host defense against N. fowleri infection, but further studies are required to elucidate the mechanisms involved in protective effects conferred by Cry1Ac, which may be a valuable tool to improve mucosal vaccines. PMID:15271892

Prevalence of Toxoplasma gondii in native donkeys in Mosul

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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.

Toxoplasma and Africa: One Parasite, Two Opposite Population Structures.

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Galal, Lokman; Ajzenberg, Daniel; Hamidović, Azra; Durieux, Marie-Fleur; Dardé, Marie-Laure; Mercier, Aurélien

2018-02-01

Exploring the genetic diversity of Toxoplasma gondii is essential for an understanding of its worldwide distribution and the determinants of its evolution. Africa remains one of the least studied areas of the world regarding T. gondii genetic diversity. This review has compiled published data on T. gondii strains from Africa to generate a comprehensive map of their continent-wide geographical distribution. The emerging picture about T. gondii strain distribution in Africa suggests a geographical separation of the parasite populations across the continent. We discuss the potential role of a number of factors in shaping this structure. We finally suggest the next steps towards a better understanding of Toxoplasma epidemiology in Africa in light of the strains circulating on this continent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Seroprevalence of Toxoplasma gondii infection among pregnant women in Cameroon

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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.

Toxoplasma depends on lysosomal consumption of autophagosomes for persistent infection.

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Di Cristina, Manlio; Dou, Zhicheng; Lunghi, Matteo; Kannan, Geetha; Huynh, My-Hang; McGovern, Olivia L; Schultz, Tracey L; Schultz, Aric J; Miller, Alyssa J; Hayes, Beth M; van der Linden, Wouter; Emiliani, Carla; Bogyo, Matthew; Besteiro, Sébastien; Coppens, Isabelle; Carruthers, Vern B

2017-06-19

Globally, nearly 2 billion people are infected with the intracellular protozoan Toxoplasma gondii 1 . This persistent infection can cause severe disease in immunocompromised people and is epidemiologically linked to major mental illnesses 2 and cognitive impairment 3 . There are currently no options for curing this infection. The lack of effective therapeutics is due partly to a poor understanding of the essential pathways that maintain long-term infection. Although it is known that Toxoplasma replicates slowly within intracellular cysts demarcated with a cyst wall, precisely how it sustains itself and remodels organelles in this niche is unknown. Here, we identify a key role for proteolysis within the parasite lysosomal organelle (the vacuolar compartment or VAC) in turnover of autophagosomes and persistence during neural infection. We found that disrupting a VAC-localized cysteine protease compromised VAC digestive function and markedly reduced chronic infection. Death of parasites lacking the VAC protease was preceded by accumulation of undigested autophagosomes in the parasite cytoplasm. These findings suggest an unanticipated function for parasite lysosomal degradation in chronic infection, and identify an intrinsic role for autophagy in the T. gondii parasite and its close relatives. This work also identifies a key element of Toxoplasma persistence and suggests that VAC proteolysis is a prospective target for pharmacological development.

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...

Persistent Low Toxoplasma IgG Avidity Is Common in Pregnancy: Experience from Antenatal Testing in Norway.

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Gry Findal

Full Text Available The parasite Toxoplasma gondii might harm the fetus if a woman is infected during pregnancy. IgG seroconversion and significant increase in IgG antibody amount in pregnancy indicates maternal infection. Presence of toxoplasma immunoglobulin M (IgM, immunoglobulin G (IgG and low IgG avidity in a single serum sample indicates possible maternal infection, but positive toxoplasma IgM and low IgG avidity may persist for months and even years. We aimed to evaluate avidity development during pregnancy in a retrospective study. Serial blood samples from 176 pregnant women admitted to Oslo University Hospital 1993-2013 for amniocentesis because of suspected toxoplasma infection were included. Data were obtained from journals and laboratory records. The avidity method used was based on Platelia Toxo IgG assay. Mean maternal age at first serology was 29.9 years (SD 5.2, range 18-42. In 37 (21% women only the avidity increased from low to high in < 3 months. In 139 (79% the IgG avidity remained below the high threshold ≥ 3 months and within this group 74 (42% women had stable low IgG avidity during the observation period. Median gestational age at first test was 10.6 weeks (range 4.6-28.7. Fetal infection was detected in four children, but none among children whose mother had stable low IgG avidity. The first antenatal toxoplasma serology should ideally be collected in early pregnancy and if stable values of toxoplasma IgM and low IgG-avidity are detected in a second sample after three to four weeks, the need for amniocentesis can be questioned.

Epidemiology and Molecular Prevalence of Toxoplasma gondii in Cattle Slaughtered in Zahedan and Zabol Districts, South East of Iran

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Davood ANVARI

2018-03-01

Full Text Available Background: Toxoplasma gondii is an obligate, intracellular parasite which causes the toxoplasmosis in humans and warm-blooded animals. Red meat is an important source for transmission of the infection to humans. This study aimed to determine the prevalence of Toxoplasma among imported and indigenous cattle in the Sistan region.Methods: One hundred samples from slaughtered cattle were collected from two abattoirs of Zabol and Zahedan, South East of Iran in 2015. Each sample was a mixture of three muscle, including tongue, cardiac, and triceps. Additional data of each cattle, including sex, breed, age, indigenous or imported, location of slaughter, management practices, and feeding system were obtained through observations and interviews. Infection by T. gondii was determined by PCR method.Results: The prevalence of Toxoplasma in indigenous cattle was 6% and in imported cattle was 26%, and this difference was statistically significant (P=0.006. Moreover, the prevalence of Toxoplasma was statistically associated with management practices (P=0.01 and feeding system (P=0.001. However, relationship between the prevalence of Toxoplasma with age, breed, sex, and location of slaughter was not statistically significant.Conclusion: Since the prevalence of Toxoplasma among imported cattle is higher than indigenous cattle, so strict supervision for importing livestock from neighboring countries is necessary.

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

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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.

Aspectos ultraestruturais do processo de divisão do Toxoplasma gondii

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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

Toxoplasma gondii seroprevalence in breeding pigs in Estonia

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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...

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

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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.

Development and application of radioimmunoassays and enzyme immunoassays in microbiological and immunological diagnosis. 2. Comparative studies for the detection of toxoplasma antibodies with ELISA, RIA and other serological methods

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Mueller, W A; Struy, H; Holzwarth, F [Medizinische Akademie, Magdeburg (German Democratic Republic)

1982-06-01

Comparative studies of indirect immunofluorescence test (IT), complement binding reaction (CBR), enzyme- and radioimmunoassay (ELISA, RIA) for the detection of toxoplasma antibodies in sera of 513 patients are reported. The precision dependent on time, showed coefficients of variation from 3% to 12% (IFT 3%, CBR 10%, ELISA 12%, RIA 7%). The correlation of IFT and ELISA as well as RIA was relatively unfavourable (coefficient of correlation IFT/ELISA r = 0.52, IFT/RIA r = 0.54, RIA/ELISA r = 0.60). The ELISA is the most sensitive method for the detection of antibodies. The specificity of the Toxo-ELISA has to be improved by application of suitable fractions of antigens.

Risk factors for Toxoplasma infection in pregnant women in FYR of Macedonia*

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Cvetković D.

2010-09-01

Full Text Available The aim of the study was to identify risk factors for Toxoplasma gondii infection in pregnant women in FYR of Macedonia. Retrospective analysis of serological and epidemiological data in a series of 235 pregnant women from Macedonia, tested for Toxoplasma infection between January 2004 and December 2005, showed an overall prevalence of infection of 20.4 %. Exposure to transmission factors significantly increased the risk of infection (RR = 1.989, 95 % CI = 1.041-3.800, p = 0.037. The single infection transmission factor that was a predictor of infection in the whole series was exposure to soil (RR = 1.946, 95 % CI = 1.026-3.692, p = 0.041. Based on prevalence and the established risk factors for Toxoplasma infection in Macedonia, the health education programme as a sustainable measure for the prevention of congenital toxoplasmosis should focus on educating women of generative age to avoid contact with soil (farming, gardening, and/to adhere to strict hygienic practices afterwards.

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

Toxoplasma gondii seroprevalence in dairy and beef cattle

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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...

Identification of Eimeria acervulina conoid antigen using chicken monoclonal antibody.

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Matsubayashi, Makoto; Minoura, Chisa; Kimura, Shintaro; Tani, Hiroyuki; Furuya, Masaru; Lillehoj, Hyun S; Matsuda, Haruo; Takenaka, Shigeo; Hatta, Takeshi; Tsuji, Naotoshi; Sasai, Kazumi

2016-11-01

In the poultry industry, Eimeria spp. is one of the important pathogens which cause significant economic losses. We have previously generated a chicken monoclonal antibody (mAb), 6D-12-G10, with specificity for an antigen located in the apical cytoskeleton of Eimeria acervulina and with cross-reactive among Apicomplexan parasites, including other Eimeria spp., Toxoplasma, Neospora, and Cryptosporidium spp. Furthermore, the protein of Cryptosporidium parvum recognized by the 6D-12-G10 has been identified as elongation factor-1α (EF-1α). In the present study, to identify the target molecule of E. acervulina by the mAb, we performed two-dimensional Western blotting analysis. Finally, we found two positive molecules which are identified as EF-1α and a related protein. Our previous finding using C. parvum and the results in this study suggest that EF-1α could be associated with the invasion facilitated by the cytoskeleton at the apical region of zoites.

Introduction of caveolae structural proteins into the protozoan Toxoplasma results in the formation of heterologous caveolae but not caveolar endocytosis.

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Bao Lige

Full Text Available Present on the plasma membrane of most metazoans, caveolae are specialized microdomains implicated in several endocytic and trafficking mechanisms. Caveolins and the more recently discovered cavins are the major protein components of caveolae. Previous studies reported that caveolar invaginations can be induced de novo on the surface of caveolae-negative mammalian cells upon heterologous expression of caveolin-1. However, it remains undocumented whether other components in the transfected cells participate in caveolae formation. To address this issue, we have exploited the protozoan Toxoplasma as a heterologous expression system to provide insights into the minimal requirements for caveogenesis and caveolar endocytosis. Upon expression of caveolin-1, Toxoplasma accumulates prototypical exocytic caveolae 'precursors' in the cytoplasm. Toxoplasma expressing caveolin-1 alone, or in conjunction with cavin-1, neither develops surface-located caveolae nor internalizes caveolar ligands. These data suggest that the formation of functional caveolae at the plasma membrane in Toxoplasma and, by inference in all non-mammalian cells, requires effectors other than caveolin-1 and cavin-1. Interestingly, Toxoplasma co-expressing caveolin-1 and cavin-1 displays an impressive spiraled network of membranes containing the two proteins, in the cytoplasm. This suggests a synergistic activity of caveolin-1 and cavin-1 in the morphogenesis and remodeling of membranes, as illustrated for Toxoplasma.

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.

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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.

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

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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

Lysate of engineered Escherichia coli supports high-level conversion of glucose to 2,3-butanediol.

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Kay, Jennifer E; Jewett, Michael C

2015-11-01

Cell-free metabolic engineering (CFME) is emerging as a powerful approach for the production of target molecules and pathway debugging. Unfortunately, high cofactor costs, limited cofactor and energy regeneration, and low volumetric productivities hamper the widespread use and practical implementation of CFME technology. To address these challenges, we have developed a cell-free system that harnesses ensembles of catalytic proteins prepared from crude lysates, or extracts, of cells to fuel highly active heterologous metabolic conversions. As a model pathway, we selected conversion of glucose to 2,3-butanediol (2,3-BD), a medium level commodity chemical with many industrial applications. Specifically, we engineered a single strain of Escherichia coli to express three pathway enzymes necessary to make meso-2,3-BD (m2,3-BD). We then demonstrated that lysates from this strain, with addition of glucose and catalytic amounts of cofactors NAD+ and ATP, can produce m2,3-BD. Endogenous glycolytic enzymes convert glucose to pyruvate, the starting intermediate for m2,3-BD synthesis. Strikingly, with no strain optimization, we observed a maximal synthesis rate of m2,3-BD of 11.3 ± 0.1 g/L/h with a theoretical yield of 71% (0.36 g m2,3-BD/g glucose) in batch reactions. Titers reached 82 ± 8 g/L m2,3-BD in a 30 h fed-batch reaction. Our results highlight the ability for high-level co-factor regeneration in cell-free lysates. Further, they suggest exciting opportunities to use lysate-based systems to rapidly prototype metabolic pathways and carry out molecular transformations when bioconversion yields (g product/L), productivities (g product/L/h), or cellular toxicity limit commercial feasibility of whole-cell fermentation. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Platelet lysate mucohadesive formulation to treat oral mucositis in graft versus host disease patients: a new therapeutic approach.

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Del Fante, Claudia; Perotti, Cesare; Bonferoni, Maria Cristina; Rossi, Silvia; Sandri, Giuseppina; Ferrari, Franca; Scudeller, Luigia; Caramella, Carla Marcella

2011-09-01

Optimal treatment of oral mucositis (OM) due to graft versus host disease (GvHD) is currently not available. Platelet-derived growth factors (PDGFs) have high capability for tissue healing and may play a role in repairing the mucosal barrier. The aim of the present work was to develop a mucoadhesive formulation to administer platelet lysate to oral cavity prolonging contact time of platelet lysate with oral mucosa. The mucoadhesive formulation was characterized for in vitro properties (PDGF-AB concentration, mucoadhesive properties, cytotoxicity, fibroblast proliferation, wound healing). Moreover, a preliminary clinical study on seven GvHD patients with OM refractory to other therapies was conducted, to evaluate feasibility, safety, and efficacy. GVPL (mucoadhesive gel vehicle mixed with platelet lysate)showed good mucoadhesive properties; additionally, it was characterized by good biocompatibility in vitro on fibroblasts and it was able to enhance fibroblast proliferation and wound healing, maintaining the efficacy for up to 14 days following storage at 2-8°C. In vivo, clinical response was good-to-complete in five, fair in one, none in the remaining one. The in vitro results indicate that GVPL has optimal mucoadhesive and healing enhancer properties, maintained over time (up to 14 days); preliminary clinical results suggest that oral application of platelet lysate-loaded mucoadhesive formulation is feasible, safe, well tolerated, and effective. A larger controlled randomized study is needed.

Serological survey of Toxoplasma gondii, Dirofilaria immitis, Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV) infections in pet cats in Bangkok and vicinities, Thailand.

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Sukhumavasi, Woraporn; Bellosa, Mary L; Lucio-Forster, Araceli; Liotta, Janice L; Lee, Alice C Y; Pornmingmas, Pitcha; Chungpivat, Sudchit; Mohammed, Hussni O; Lorentzen, Leif; Dubey, J P; Bowman, Dwight D

2012-08-13

The seroprevalence of Toxoplasma gondii, Dirofilaria immitis (heartworm), feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infections was examined using serum or plasma samples from 746 pet cats collected between May and July 2009 from clinics and hospitals located in and around Bangkok, Thailand. The samples were tested for heartworm, FIV, and FeLV using a commercial ELISA. Of the 746 samples, 4.6% (34/746) were positive for heartworm antigen, 24.5% (183/746) had circulating FeLV antigen, and 20.1% (150/746) had antibodies against FIV. In addition, the first 348 submitted samples were tested for T. gondii antibodies using a modified agglutination test (MAT, cut off 1:25); 10.1% (35/348) were seropositive. Of the 348 cats sampled for all four pathogens, 11, 10, and 1 were positive for T. gondii antibodies and FIV antibodies, FeLV antigen, or D. immitis antigen, respectively. Of the 35 T. gondii-seropositive cats, 42.9% (15/35) were co-infected with at least one of the other three pathogens. The presence of antibodies to FIV was significantly associated with both age and gender, while FeLV antigen presence was only associated with age. In the case of FIV, males were twice as likely to be infected as females, and cats over 10 years of age were 13.5 times more likely to be infected than cats less than 1 year of age. FeLV antigen was more common in younger cats, with cats over 10 years of age being 10 times less likely to be FeLV positive than cats under 1 year of age. This is the first survey for these four pathogens affecting feline health in Thailand. Copyright © 2012 Elsevier B.V. All rights reserved.

[Advances in researches on mechanism of anti-Toxoplasma Chinese herbal medicine].

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Yu, Zhao-Yun; Zhang, Bao-de; Ning, Jun-ya; Wang, Yuan-yuan; Yuan, Wen-ying

2015-10-01

Toxoplasma gondii is an opportunity cellular parasite, related to the infection of various animals and human beings and severely impairing agriculture and human health. Because of the complexity of T. gondii life cycle, its different biological characteristics, and multifarious pathogenesis, there are no specific treatment and preventive medicines at present. Chinese herbal medicine can balance "yin-yang" and regulate the immunity and its side-effect is slight. Now, it has been a hot topic of the research on effective and secure medicines in anti-toxoplasmosis. This paper summarizes and analyzes the curative effect and mechanism of anti-Toxoplasma Chinese herbal medicine, such as Scutellaria baicalensis, Inontus obliquus polysaccharide, Radix glycyrrhizae, pumpkin seeds, and Semen arecae.

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

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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.

SEROEPIDEMIOLOGY OF TOXOPLASMA, RUBELLA, CYTOMEGALOVIRUS AND HERPES SIMPLEX VIRUS -2 IN WOMEN WITH BAD OBSTETRIC HISTORY. PART I: TOXOPLASMA AND RUBELLA INFECTIONS

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Abdulghani Mohamed Alsamarai

2013-10-01

Full Text Available Bad obstetric history (BOH is associated with social and psychological impacts on society worldwide. The causes of BOH may be genetic, hormonal, abnormal maternal immune response, and maternal infection. In women with bad obstetric history (BOH, Toxoplasma (T IgG high rate has been reported for Nepal (55.2%, while high (42.5% and lowest (6.97% active toxoplasma infections has been reported for India. In Arab countries, IgG and IgM higher and lowest seroprevalence rates were for Iraq. The higher susceptibility rates for Rubella in Arab countries excluding Iraq were reported in Morocco (83.4%, Sudan (34.7%, Qatar (25.1%, and Tunisia (20.3%. The lowest susceptibility was reported for Saudi Arabia (6.7%. In Iraq, studies indicate a high susceptibility rates in Thi Qar (98.05%, Kirkuk (91%, Baghdad (79%, and Waset (45.7%. The lowest susceptibility rates were reported for Diyala (0% in women with previous abortion, and 3.9% in pregnant women without history of BOH.

Detection of Toxoplasma gondii oocysts in water: proposition of a strategy and evaluation in Champagne-Ardenne Region, France

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D Aubert

2009-03-01

Full Text Available Water is a vehicle for disseminating human and veterinary toxoplasmosis due to oocyst contamination. Several outbreaks of toxoplasmosis throughout the world have been related to contaminated drinking water. We have developed a method for the detection of Toxoplasma gondii oocysts in water and we propose a strategy for the detection of multiple waterborne parasites, including Cryptosporidium spp. and Giardia. Water samples were filtered to recover Toxoplasma oocysts and, after the detection of Cryptosporidium oocysts and Giardia cysts by immunofluorescence, as recommended by French norm procedure NF T 90-455, the samples were purified on a sucrose density gradient. Detection of Toxoplasma was based on PCR amplification and mouse inoculation to determine the presence and infectivity of recovered oocysts. After experimental seeding assays, we determined that the PCR assay was more sensitive than the bioassay. This strategy was then applied to 482 environmental water samples collected since 2001. We detected Toxoplasma DNA in 37 environmental samples (7.7%, including public drinking water; however, none of them were positive by bioassay. This strategy efficiently detects Toxoplasma oocysts in water and may be suitable as a public health sentinel method. Alternative methods can be used in conjunction with this one to determine the infectivity of parasites that were detected by molecular methods.

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

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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.

Comparison of Eight Cell-Free Media for Maintenance of Toxoplasma gondii Tachyzoites

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Hamed KALANI

2016-03-01

Full Text Available Background: Toxoplasmosis is considered as one of the most common infectious diseases caused by the protozoan parasite Toxoplasma gondii. Tachyzoite is the main form of Toxoplasma and continuously is maintained in cell culture or injected into the mice peritoneal cavity. This study was designed to evaluate the survival rate of RH strain of T. gondii tachyzoites in different cell free, nutrient and biological media at different temperatures.Methods: This experimental study was performed at the Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran, in 2010. One ml of each solution including hypotonic saline (0.3%, normal saline (0.85%, RPMI-1640 (RPMI, RPMI with 10% fetal bovine serum (FBS, RPMI with 20% FBS, ovine hydatid cyst fluid, pasteurized milk of cow, and phosphate buffered saline (PBS along with 4×104 T. gondii tachyzoites were added to plate wells and incubated in 4 °C, 22 °C, 37 °C, and 37 °C under 5% CO2. The survival rate and viability as­sessment of parasites were performed daily and the results were analyzed using Univariate tests.Result: Tachyzoites survival rate in PBS (4 °C and normal saline (4 °C were con­siderably high, compared to other solutions in different conditions (P<0.001. The best temperature for Toxoplasma maintenance was 4 °C (P<0.001.Conclusion: This study introduces two available and economical solutions, PBS (4 °C and normal saline (4 °C media, for maintenance of Toxoplasma tachyzoites as appropriate choice media for a noticeable period of time (11 days in vitro.

Freeze-thaw lysates of Plasmodium falciparum-infected red blood cells induce differentiation of functionally competent regulatory T cells from memory T cells.

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Finney, Olivia C; Lawrence, Emma; Gray, Alice P; Njie, Madi; Riley, Eleanor M; Walther, Michael

2012-07-01

In addition to naturally occurring regulatory T (nTreg) cells derived from the thymus, functionally competent Treg cells can be induced in vitro from peripheral blood lymphocytes in response to TCR stimulation with cytokine costimulation. Using these artificial stimulation conditions, both naïve as well as memory CD4(+) T cells can be converted into induced Treg (iTreg) cells, but the cellular origin of such iTreg cells in vivo or in response to more physiologic stimulation with pathogen-derived antigens is less clear. Here, we demonstrate that a freeze/thaw lysate of Plasmodium falciparum schizont extract (PfSE) can induce functionally competent Treg cells from peripheral lymphocytes in a time- and dose-dependent manner without the addition of exogenous costimulatory factors. The PfSE-mediated induction of Treg cells required the presence of nTreg cells in the starting culture. Further experiments mixing either memory or naïve T cells with antigen presenting cells and CFSE-labeled Treg cells identified CD4(+) CD45RO(+) CD25(-) memory T cells rather than Treg cells as the primary source of PfSE-induced Treg cells. Taken together, these data suggest that in the presence of nTreg cells, PfSE induces memory T cells to convert into iTreg cells that subsequently expand alongside PfSE-induced effector T cells. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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 ...

Effectiveness of health education on Toxoplasma-related knowledge, behaviour, and risk of seroconversion in pregnancy.

Science.gov (United States)

Gollub, Erica L; Leroy, Valériane; Gilbert, Ruth; Chêne, Geneviève; Wallon, Martine

2008-02-01

We conducted a bibliographic literature search using MEDLINE to review the effectiveness of health education on Toxoplasma-related knowledge, behaviour, and risk of seroconversion in pregnant women. We pre-selected studies that used comparative study designs (randomized clinical trial, quasi-experimental design or historical control), that were conducted among pregnant women, and which employed specific, Toxoplasma-related outcome measures: knowledge, behaviour, or Toxoplasma infection rate. Four studies met the inclusion criteria. All had serious methodological flaws. A Belgian study reported a significant decrease in the incidence of Toxoplasma seroconversion after the introduction of intensive counselling for pregnant women about toxoplasmosis. In Poland, a significant increase in knowledge was observed after a multi-pronged, public health educational program was launched. In Canada, an increase in knowledge and prevention behaviours was reported in the intervention group receiving counselling by trained facilitators compared with the control group. In France, no significant changes in risk behaviour were observed following a physician-delivered intervention. This review highlights the weakness of the literature in the area and the lack of studies measuring actual seroconversion. There is suggestive evidence that health education approaches may help reduce risk of congenital toxoplasmosis but this problem requires further study using more rigorous research design and methodology.

Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture

International Nuclear Information System (INIS)

Yoshito, Daniele

2011-01-01

For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

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....

Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia.

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Janikashvili, Nona; LaCasse, Collin J; Larmonier, Claire; Trad, Malika; Herrell, Amanda; Bustamante, Sara; Bonnotte, Bernard; Har-Noy, Michael; Larmonier, Nicolas; Katsanis, Emmanuel

2011-02-03

Therapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4(+) T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4(+)CD25(+)FoxP3(+) regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3(+) Tregs from naive CD4(+)CD25(-)FoxP3(-) T cells by an interferon-γ-dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with a chaperone-rich cell lysate (CRCL) vaccine, leading to improved survival and long-lasting protection against leukemia. The combination of CRCL as a source of tumor-specific antigens and Th-1 lymphocytes as an adjuvant has the potential to stimulate efficient specific antitumor immunity while restraining Treg-induced suppression.

A biocoagulant slow sand filtration for disinfection of Toxoplasma ...

African Journals Online (AJOL)

An integrated low-tech biocoagulant-sand filter drum for disinfection of oocysts of Toxoplasma gondii targeted for developing countries was evaluated. Dirty and turbid water (130.3 NTU) from Mezam River and leachates from dump sites and stagnant water in Bamenda, Cameroon, was analyzed microscopically after ...

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 ...

Seroprevalence of antibody to TgGRA7 antigen of Toxoplasma gondii in livestock animals from Western Java, Indonesia.

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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.

Human platelet lysate: Replacing fetal bovine serum as a gold standard for human cell propagation?

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Burnouf, Thierry; Strunk, Dirk; Koh, Mickey B C; Schallmoser, Katharina

2016-01-01

The essential physiological role of platelets in wound healing and tissue repair builds the rationale for the use of human platelet derivatives in regenerative medicine. Abundant growth factors and cytokines stored in platelet granules can be naturally released by thrombin activation and clotting or artificially by freeze/thaw-mediated platelet lysis, sonication or chemical treatment. Human platelet lysate prepared by the various release strategies has been established as a suitable alternative to fetal bovine serum as culture medium supplement, enabling efficient propagation of human cells under animal serum-free conditions for a multiplicity of applications in advanced somatic cell therapy and tissue engineering. The rapidly increasing number of studies using platelet derived products for inducing human cell proliferation and differentiation has also uncovered a considerable variability of human platelet lysate preparations which limits comparability of results. The main variations discussed herein encompass aspects of donor selection, preparation of the starting material, the possibility for pooling in plasma or additive solution, the implementation of pathogen inactivation and consideration of ABO blood groups, all of which can influence applicability. This review outlines the current knowledge about human platelet lysate as a powerful additive for human cell propagation and highlights its role as a prevailing supplement for human cell culture capable to replace animal serum in a growing spectrum of applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

On the determination of Toxoplasma gondii virulence in mice

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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...

Confocal microscope is able to detect calcium metabolic in neuronal infection by toxoplasma gondii

International Nuclear Information System (INIS)

Sensusiati, A D; Priya, T K S; Dachlan, Y P

2017-01-01

Calcium metabolism plays a very important role in neurons infected by Toxoplasma. Detection of change of calcium metabolism of neuron infected by Toxoplasma and Toxoplasma requires the calculation both quantitative and qualitative method. Confocal microscope has the ability to capture the wave of the fluorescent emission of the fluorescent dyes used in the measurement of cell calcium. The purpose of this study was to prove the difference in calcium changes between infected and uninfected neurons using confocal microscopy. Neuronal culture of human-skin-derived neural stem cell were divided into 6 groups, consisting 3 uninfected groups and 3 infected groups. Among the 3 groups were 2 hours, 24 hours and 48 hours. The neuron Toxoplasma gondii ratio was 1:5. Observation of intracellular calcium of neuron and tachyzoite, evidence of necrosis, apoptosis and the expression of Hsp 70 of neuron were examined by confocal microscope. The normality of the data was analysed by Kolmogorov-Smirnov Test, differentiation test was checked by t2 Test, and ANOVAs, for correlation test was done by Pearson Correlation Test. The calcium intensity of cytosolic neuron and T. gondii was significantly different from control groups (p<0.05). There was also significant correlation between calcium intensity with the evidence of necrosis and Hsp70 expression at 2 hours after infection. Apoptosis and necrosis were simultaneously shown with calcium contribution in this study. Confocal microscopy can be used to measure calcium changes in infected and uninfected neurons both in quantitatively and qualitatively. (paper)

The effect of platelet lysate supplementation of a dextran-based hydrogel on cartilage formation

NARCIS (Netherlands)

Moreira Teixeira, Liliana; Leijten, Jeroen Christianus Hermanus; Wennink, J.W.H.; Ganguly, Anindita; Feijen, Jan; van Blitterswijk, Clemens; Dijkstra, Pieter J.; Karperien, Hermanus Bernardus Johannes

2012-01-01

In situ gelating dextran-tyramine (Dex-TA) injectable hydrogels have previously shown promising features for cartilage repair. Yet, despite suitable mechanical properties, this system lacks intrinsic biological signals. In contrast, platelet lysate-derived hydrogels are rich in growth factors and

Platelet Lysate: The Better Choice for Jaw Periosteal Cell Mineralization

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Yvonne Wanner

2017-01-01

Full Text Available Previously, we demonstrated a high quality of minerals formed by serum-free cultured jaw periosteal cells (JPCs by Raman spectroscopy but the mineralization extent was not satisfactory. In the present study, we analyzed the proliferation and mineralization potential of human platelet lysate- (hPL- cultured JPCs in comparison to that of FCS-cultured JPCs. By cell impedance measurements, we detected significantly higher population doubling times of PL-cultured JPCs in comparison to FCS-cultured JPCs. However, this result was not based on lower proliferation activities but on diminished cell sizes which JPCs develop under PL cultivation. The measurements of the metabolic activities clearly showed significantly higher cell proliferation rates under PL culturing. Equivalent levels of the mesenchymal cell markers CD29, CD45, CD73, CD90, and CD105 were detected, but there were significantly increased MSCA-1 levels under PL cultivation. While JPCs only occasionally mineralize under FCS culture conditions, the mineralization potential was significantly stronger under PL cultivation. Moreover, in 4 of 5 analyzed patient cells, the addition of dexamethasone was proved no longer necessary for strong mineralization of PL-cultured JPCs. We conclude that in vitro cultivation of JPCs with platelet lysate is a suitable alternative to FCS culture conditions and a powerful tool for the development of high-quality TE constructs using jaw periosteal cells.

Platelet Lysate: The Better Choice for Jaw Periosteal Cell Mineralization.

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Wanner, Yvonne; Umrath, Felix; Waidmann, Marc; Reinert, Siegmar; Alexander, Dorothea

2017-01-01

Previously, we demonstrated a high quality of minerals formed by serum-free cultured jaw periosteal cells (JPCs) by Raman spectroscopy but the mineralization extent was not satisfactory. In the present study, we analyzed the proliferation and mineralization potential of human platelet lysate- (hPL-) cultured JPCs in comparison to that of FCS-cultured JPCs. By cell impedance measurements, we detected significantly higher population doubling times of PL-cultured JPCs in comparison to FCS-cultured JPCs. However, this result was not based on lower proliferation activities but on diminished cell sizes which JPCs develop under PL cultivation. The measurements of the metabolic activities clearly showed significantly higher cell proliferation rates under PL culturing. Equivalent levels of the mesenchymal cell markers CD29, CD45, CD73, CD90, and CD105 were detected, but there were significantly increased MSCA-1 levels under PL cultivation. While JPCs only occasionally mineralize under FCS culture conditions, the mineralization potential was significantly stronger under PL cultivation. Moreover, in 4 of 5 analyzed patient cells, the addition of dexamethasone was proved no longer necessary for strong mineralization of PL-cultured JPCs. We conclude that in vitro cultivation of JPCs with platelet lysate is a suitable alternative to FCS culture conditions and a powerful tool for the development of high-quality TE constructs using jaw periosteal cells.

Cell Death of Gamma Interferon-Stimulated Human Fibroblasts upon Toxoplasma gondii Infection Induces Early Parasite Egress and Limits Parasite Replication

NARCIS (Netherlands)

Niedelman, Wendy; Sprokholt, Joris K.; Clough, Barbara; Frickel, Eva-Maria; Saeij, Jeroen P. J.

2013-01-01

The intracellular protozoan parasite Toxoplasma gondii is a major food-borne illness and opportunistic infection for the immunosuppressed. Resistance to Toxoplasma is dependent on gamma interferon (IFN-γ) activation of both hematopoietic and nonhematopoietic cells. Although IFN-γ-induced innate

Cell death of gamma interferon-stimulated human fibroblasts upon toxoplasma gondii infection induces early parasite egress and limits parasite replication

NARCIS (Netherlands)

Niedelman, W.; Sprokholt, J.K.; Clough, B.; Frickel, E.; Saeij, J.P.J.

2013-01-01

The intracellular protozoan parasite Toxoplasma gondii is a major food-borne illness and opportunistic infection for the immunosuppressed. Resistance to Toxoplasma is dependent on gamma interferon (IFN-¿) activation of both hematopoietic and nonhematopoietic cells. Although IFN-¿-induced innate

Composition of growth factors and cytokines in lysates obtained from fresh versus stored pathogen-inactivated platelet units.

Science.gov (United States)

Sellberg, Felix; Berglund, Erik; Ronaghi, Martin; Strandberg, Gabriel; Löf, Helena; Sommar, Pehr; Lubenow, Norbert; Knutson, Folke; Berglund, David

2016-12-01

Platelet lysate is a readily available source of growth factors, and other mediators, which has been used in a variety of clinical applications. However, the product remains poorly standardized and the present investigation evaluates the composition of platelet lysate obtained from either fresh or stored pathogen-inactivated platelet units. Platelet pooled units (n = 10) were obtained from healthy blood donors and tested according to standard procedures. All units were pathogen inactivated using amotosalen hydrochloride and UVA exposure. Platelet lysate was subsequently produced at two separate time-points, either from fresh platelet units or after 5 days of storage, by repeated freeze-thaw cycles. The following mediators were determined at each time-point: EGF, FGF-2, VEGF, IGF-1, PDGF-AB/BB, BMP-2, PF4, TGF-β isoform 1, IL-1β, IL-2, IL-6, IL-10, IL-12p70, 1L-17A, TNF-α, and IFN-γ. The concentration of growth factors and cytokines was affected by time in storage. Notably, TGF-β, PDGF-AB/BB, and PF4 showed an increase of 27.2% (p product, which potentially may influence the clinical effects. Copyright © 2016. Published by Elsevier Ltd.

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.

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

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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

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...

Point-of-care testing for Toxoplasma gondii IgG/IgM using Toxoplasma ICT IgG-IgM test with sera from the United States and implications for developing countries.

Science.gov (United States)

Begeman, Ian J; Lykins, Joseph; Zhou, Ying; Lai, Bo Shiun; Levigne, Pauline; El Bissati, Kamal; Boyer, Kenneth; Withers, Shawn; Clouser, Fatima; Noble, A Gwendolyn; Rabiah, Peter; Swisher, Charles N; Heydemann, Peter T; Contopoulos-Ioannidis, Despina G; Montoya, Jose G; Maldonado, Yvonne; Ramirez, Raymund; Press, Cindy; Stillwaggon, Eileen; Peyron, François; McLeod, Rima

2017-06-01

Congenital toxoplasmosis is a serious but preventable and treatable disease. Gestational screening facilitates early detection and treatment of primary acquisition. Thus, fetal infection can be promptly diagnosed and treated and outcomes can be improved. We tested 180 sera with the Toxoplasma ICT IgG-IgM point-of-care (POC) test. Sera were from 116 chronically infected persons (48 serotype II; 14 serotype I-III; 25 serotype I-IIIa; 28 serotype Atypical, haplogroup 12; 1 not typed). These represent strains of parasites infecting mothers of congenitally infected children in the U.S. 51 seronegative samples and 13 samples from recently infected persons known to be IgG/IgM positive within the prior 2.7 months also were tested. Interpretation was confirmed by two blinded observers. A comparison of costs for POC vs. commercial laboratory testing methods was performed. We found that this new Toxoplasma ICT IgG-IgM POC test was highly sensitive (100%) and specific (100%) for distinguishing IgG/IgM-positive from negative sera. Use of such reliable POC tests can be cost-saving and benefit patients. Our work demonstrates that the Toxoplasma ICT IgG-IgM test can function reliably as a point-of-care test to diagnose Toxoplasma gondii infection in the U.S. This provides an opportunity to improve maternal-fetal care by using approaches, diagnostic tools, and medicines already available. This infection has serious, lifelong consequences for infected persons and their families. From the present study, it appears a simple, low-cost POC test is now available to help prevent morbidity/disability, decrease cost, and make gestational screening feasible. It also offers new options for improved prenatal care in low- and middle-income countries.

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.

High prevalence of anti-toxoplasma antibodies and absence of Toxoplasma gondii infection risk factors among pregnant women attending routine antenatal care in two Hospitals of Addis Ababa, Ethiopia

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Woyneshet Gelaye

2015-05-01

Conclusion: Prevalence of toxoplasmosis among pregnant women in Addis Ababa, Ethiopia is higher than that reported from other countries. Efforts to describe risk factors for toxoplasma infection among Ethiopians should focus in children.

Combinations of SPR and MS for Characterizations of Native and Recombinant Proteins in Cell Lysates

DEFF Research Database (Denmark)

Borch, Jonas; Roepstorff, Peter

2006-01-01

Surface plasmon resonance and mass spectrometry (SPR-MS) has been combined for quality check of recombinant 6xHis-tagged 14-3-3 proteins expressed in Escherichia coli. Lysates were injected over an SPR sensorchip with immobilized Ni2+ for SPR analysis of the specific Ni2+ binding response...... and stability. To validate the identity, intactness and homogeneity of the captured proteins were eluted for mass spectrometric analysis of intact molecular weight and peptide mass mapping. Additionally, the captured recombinant proteins were investigated for specific binding to known phosphorylated ligands...... of 14-3-3 proteins in order to test their activity. Specific binding of recombinant and native 14-3-3 proteins in complex mixtures to immobilized phosphopeptides and subsequent elution was also tested by SPR-MS. Ammonium sulfate precipitate fractions from lysates of E. coli expressing 14-3-3 protein...

Toxoplasma gondii and schizophrenia: a review of published RCTs.

Science.gov (United States)

Chorlton, Sam D

2017-07-01

Over the last 60 years, accumulating evidence has suggested that acute, chronic, and maternal Toxoplasma gondii infections predispose to schizophrenia. More recent evidence suggests that chronically infected patients with schizophrenia present with more severe disease. After acute infection, parasites form walled cysts in the brain, leading to lifelong chronic infection and drug resistance to commonly used antiparasitics. Chronic infection is the most studied and closely linked with development and severity of schizophrenia. There are currently four published randomized controlled trials evaluating antiparasitic drugs, specifically azithromycin, trimethoprim, artemisinin, and artemether, in patients with schizophrenia. No trials have demonstrated a change in psychopathology with adjunctive treatment. Published trials have either selected drugs without evidence against chronic infection or used them at doses too low to reduce brain cyst burden. Furthermore, trials have failed to achieve sufficient power or account for confounders such as previous antipsychotic treatment, sex, age, or rhesus status on antiparasitic effect. There are currently no ongoing trials of anti-Toxoplasma therapy in schizophrenia despite ample evidence to justify further testing.

Association of Alpha Tocopherol and Ag Sulfadiazine Chitosan Oleate Nanocarriers in Bioactive Dressings Supporting Platelet Lysate Application to Skin Wounds.

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Bonferoni, Maria Cristina; Sandri, Giuseppina; Rossi, Silvia; Dellera, Eleonora; Invernizzi, Alessandro; Boselli, Cinzia; Cornaglia, Antonia Icaro; Del Fante, Claudia; Perotti, Cesare; Vigani, Barbara; Riva, Federica; Caramella, Carla; Ferrari, Franca

2018-02-09

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds.

Association of Alpha Tocopherol and Ag Sulfadiazine Chitosan Oleate Nanocarriers in Bioactive Dressings Supporting Platelet Lysate Application to Skin Wounds

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Maria Cristina Bonferoni

2018-02-01

Full Text Available Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds.

[Serological survey on Toxoplasma gondii infection in pregnant women with history of adverse pregnancy in Bazhou area, Hebei Province].

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Ming-Hui, Zhu; Li-Juan, Xu; Zhen-Wei, Xue

2016-06-22

To investigate the Toxoplasma gondii infection status in pregnant women with history of adverse pregnancy and risk factors in Bazhou area, Hebei Province. A total of 302 pregnant women with the history of adverse pregnancy were chosen as respondents (an experimental group) in the hospital from March 2012 to December 2015, and 197 pregnant women without the history of adverse pregnancy as a control group. TOX-IgG and TOX-IgM were detected by using ELISA in two groups. The risk factors of Toxoplasma infection were surveyed by questionnaires. The total positive rate of Toxoplasma antibodies was 28.15% (85/302) in the experimental group, which was significantly higher than that [9.64%(19/197)] in the control group, and the difference was statistically significant ( χ 2 = 24.76, P ＜0.05). The positive rates of TOX-IgM, TOX-IgG and TOX-IgM + TOX-IgG were 6.95% (21/302), 18.54% (56/302), and 2.65% (8/302) respectively in the experimental group, which were higher than 2.03% (4/197), 7.61% (15/197), and 0% (0/197) respectively in the control group ( χ 2 = 6.07, 11.67, 3.76, all P ＜0.05). The questionnaire survey showed that the proportions of keeping pets, cutting board regardless, liking to eat hot pot or barbecue, eating raw meat, often eating in the restaurant in the pregnant women with Toxoplasma infection were higher than those in the pregnant women without Toxoplasma infection, and the differences were statistically significant ( χ 2 = 22.57, 3.96, 5.87, 7.40, 4.86, all P ＜0.05), and therefore, the above unhealthy habits may be important risk factors. Toxoplasma infection could lead to adverse pregnancy outcomes. Therefore, the above-mentioned unhealthy habits should be avoided, especially during pregnancy period.

Platelet lysate as an autologous alternative for fetal bovine serum in cardiovascular tissue engineering

NARCIS (Netherlands)

Riem Vis, P.W.; Bouten, C.V.C.; Sluijter, J.P.G.; Herwerden, van L.A.; Kluin, J.

2010-01-01

There is an ongoing search for alternative tissue culture sera to engineer autologous tissues, since use of fetal bovine serum (FBS) is limited under Good Tissue Practice (GTP) guidelines. We compared FBS with human Platelet-lysate (PL) in media for in vitro cell culture. A threefold increase in

Avaliação sorológica para Toxoplasma gondii pela imunofluorescência indireta e detecção do vírus da imunodeficiência felina pela nested PCR em felinos selvagens Serological evaluation for Toxoplasma gondii by indirect immunofluorescence and detection of feline immunodeficiency virus by nested PCR in wild felines

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A.V. Rivetti Jr.

2008-10-01

Full Text Available Nineteen sera and blood samples from wild feline kept in captivity were tested for Toxoplasma gondii antibody and presence of feline immunodeficiency virus (FIV DNA, respectively. Eighteen (94.7% of the them were seropositive for toxoplasma. However, the only negative animal, a Leopardus pardalis, was the only FIV positve. These results suggest that the infection by FIV may have compromised its immune system and interfered with antibody production for toxoplasma.

Seroprevalence of Toxoplasma gondii in southern districts of Tamil Nadu using IgG-ELISA.

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Sucilathangam, G; Palaniappan, N; Sreekumar, C; Anna, T

2012-10-01

The present study was conducted to assess the seroprevalence of Toxoplasma gondii in and around Tirunelveli by in-house IgG assay using ELISA. Serum samples from 175 immunodeficient and 175 immunocompetent patients were collected at Tirunelveli district, Tamil Nadu from May 2006 to October 2007. They were subjected into in-house IgG assay using enzyme-linked immune sorbent assay (ELISA) in which tachyzoite soluble antigen derived from solubilised whole organisms was used. Out of 350 patients tested by IgG ELISA, 46 patients (13.14%) had antibodies for toxoplasmosis with mean OD value of 0.2 ± 0.073 and the OD value ranged from 0.144 to 0.444. Among the immunocompetent group of 175 patients, 19 patients (10.86%) had antibodies to toxoplasmosis whereas, in immunodeficient group of 175 patients, 27 patients (15.43%) had antibodies for toxoplasmosis. There was no statistical difference (P > 0.05) between the immunocompetent and immunodeficient group. The sensitivity and specificity of IgG ELISA in detecting toxoplasmosis was 90 and 100%, respectively. The overall seroprevalence of toxoplasmosis in and around Tirunelveli district of Tamil Nadu was 13.14% based on IgG ELISA. The study has proved ELISA to be a sensitive and specific procedure for the serodiagnosis of toxoplasmosis.

Analysis of the association opportunistic infections with c-reactive protein focus toxoplasma, cytomegalovirus, rubella,and hepatitis in human immunodeficiency virus

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Khadijah, K. H.; Ferica, K.; Katu, S.; Halim, R.; Mubin, A. H.

2018-03-01

Opportunistic infections occur more often severe in people with HIV. C-reactive protein is known to have a prognostic value in HIV and those with HIV-related opportunistic infections. High level of CRP will increase therisk of infection toxoplasma, CMV, rubella,and hepatitis in HIV.Analyzing association of opportunistic infections toxoplasma, CMV, rubella,and hepatitis with the level of CRP in HIV, a cross-sectional analytic study wasduring January-July 2017 on both outpatientand inpatient HIV subjects at Wahidin Sudirohusodo Hospital, Makassar. Each HIV patient is categorized into agroup of opportunistic infections: toxoplasma, CMV, rubella, hepatitis. CRP levels will be assessed in each group, defined by normal values 0.05).

Commensal oral bacteria antigens prime human dendritic cells to induce Th1, Th2 or Treg differentiation.

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Kopitar, A N; Ihan Hren, N; Ihan, A

2006-02-01

In various immunopathologic conditions, bacterial flora induce an immune response which results in inflammatory manifestations, e.g. periapical granuloma. Dendritic cells provide the main orchestration of specific immune responses. The aim of our study was to test the capacity of distinct oral bacterial antigens (prepared from Streptococcus mitis, Propionibacterium acnes, and Bacteroides spp.) to prime human dendritic cells for stimulation of the T-lymphocyte response. To assess the T-lymphocyte response, the expression of CD25, CD69, intracellular interferon gamma (cIFN-gamma), and intracellular interleukin 4 (cIL-4) was determined. Dendritic cells were prepared from leukocyte buffy coat from healthy blood donors. Monocytes were stimulated with IL-4 and GM-CSF and dendritic cells activated with bacterial lysates. Cell suspensions contained up to 90% dendritic cells, which represented 2-12% of the initial number of mononuclear cells. Lymphocyte subsets that developed in lymphocyte cultures after 1 week of stimulation were analyzed by flow cytometry. Dendritic cells, primed with antigens of Bacteroides fragilis have shown significantly higher activation and expression of intercellular IFN-gamma by T lymphocytes compared to negative controls. The dendritic cells primed with antigens of P. acnes had no effect on T-lymphocyte activation or cytokine production; instead they induced differentiation of T lymphocytes into CD25bright cells (regulatory T cells) with a potentially inhibitory effect on immune response. Dendritic cells primed with antigens of S. mitis induced increased expression of cIL-4. We conclude that commensal oral bacteria antigens prepared from B. fragilis, S. mitis, and P. acnes prime human dendritic cells to induce Th1, Th2, and T(reg) differentiation, respectively. This may advance our understanding of immunopathologic manifestations in the oral cavity and offer new possibilities for redirecting immune responses in mucosal vaccination.

Screening of Pregnant Women for Anti-Toxoplasma Antibodies and their Newborn for Vertical Transmission

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Aysha Yasmeen

2017-10-01

Full Text Available Introduction: Toxoplasmosis is a world-wide protozoan-zoonosis caused by Toxoplasma gondii (T. gondii. Primary infections during pregnancy may result in miscarriages, still births, and congenital malformations in the new born. Studies on vertical transmission of toxoplasmosis from India are lacking. Aim: To estimate the seroprevalence of antibodies to T. gondii among pregnant women from the rural population of Kolar and to document vertical transmissions, if any. Materials and Methods: Anti-Toxoplasma IgG levels were estimated among 251 women admitted for labour at a tertiary care hospital in Kolar, Karnataka, between December 2014 and October 2016, by Enzyme Linked Immunosorbent Assay (ELISA. Demographic, socio-economic, and obstetrical data along with exposure to risk factors among the participants were recorded. Two hundred and fifty one cord blood samples of the newborns of the above mothers were tested for anti-Toxoplasma IgM antibodies by µ capture ELISA. The validity of an IgM positive reaction was evaluated. The differences in proportions were analysed by the Chi-square test and the differences in means were analysed by the unpaired t-test. A p-value <0.05 was considered significant. Results: IgG antibodies to T. gondii could be detected in 53 (21.1% of the mothers tested; the titres ranged between 35 IU/ml – 350 IU/ml. Mothers from lower socio-economic strata had significantly higher prevalence as compared to mothers from middle classes. The seropositivity was not significantly associated with gravid status, literacy, occupation, exposure to cats, consumption of raw meat, salad, or drinking untreated water, gestational age, previous history of abortion or the mode of delivery. Cord blood samples from 5 (2 % of the newborns gave positive IgM reactions, but they were interpreted as false positives as there was no evidence of infection in their respective mothers or the baby lacked antibodies on follow up. Conclusion: About one fifth of

Seroprevalence of anti-Toxoplasma gondii and anti-Borrelia species antibodies in patients with schizophrenia: a case-control study from western Turkey.

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Cevizci, Sibel; Celik, Merve; Akcali, Alper; Oyekcin, Demet Gulec; Sahin, Ozlem Oztürk; Bakar, Coskun

2015-06-01

We examined IgG antibody seroprevalence and risk factors for anti-Toxoplasma gondii and anti-Borrelia sp. in schizophrenic patients. This case-control study included 30 schizophrenic patients and 60 healthy individuals. Serological analyses were identified by using ELISA technique. In the case group the Toxoplasma seropositivity was 33.3% and Borrelia seropositivity was 13.3%, while in the control group the Toxoplasma positivity was 21.7% and Borrelia seropositivity was 15.0%. There was no significant difference with regard to seroprevalence between the groups (P = 0.232; P = 0.832, respectively). There was statistically significant difference between case and control groups related to hand and kitchen utensil hygiene after dealing with raw meat (P = 0.001). Our data showed the rate of Toxoplasma antibodies was higher in the case group, while the rate of Borrelia antibodies was higher in the control group. In both groups the high rates of seropositivity for Toxoplasma gondii and Borrelia sp. is thought to be due to neglect of personal hygiene. The present study also is the first to examine the association between Borrelia sp. and schizophrenia. Further studies are needed to determine whether there is an association between Borrelia sp. and schizophrenia or not.

Lankesterella alencari n. sp., a toxoplasma-like organism in the central nervous system of Amphibia (Protozoa, Sporozoa Lankesterella alencari n. sp., um toxoplasma-like no sistema nervoso central de Amphibia (Protozoa, Sporozoa

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Sylvio Celso Gonçalves da Costa

1971-01-01

Full Text Available Lankesterella alencari n. sp. a Sporozoa that occur in the blood and CNS of the South American frog Leptodactylus acellatus is described. Since the tissue forms of this parasite have been previously reported as belonging to the genus Toxoplasma, we attempted in fection of 2 species of amphibia (Bufo marinus an dLeptodactylus ocellatus with a Toxoplasma strain of human origen; inoculation was by intraperitoneal injection of parasite-containing ascitic fluid from infected mice. Attempt of experimental inoculation of the parasite found in the CNS of L. ocellatus in a highly susceptible host (mice was unsuccessful. These results suggest that Toxoplasma does not occur naturally in the amphibia; be related to Toxoplasma is excluded. The following genera of haematozoa found in brazilian amphibia have been considered briedfly: Haemobartonella, Cytamoeba, Dactylosoma, Hepatozoon and Trypanosoma.Os autores descrevem uma espécie do gênero Lankesterella considerada nova para a ciência, que ocorre com certa freqüência parasitando a rã Leptodactylus ocellatus no Brasil. Como os cistos dêste parasito, encontrados no SNC, foram anteriormente relacionados ao gênero Toxoplasma por outro autor, realizamos uma série de inoculações experimentais para eliminar a hipótese. Tanto as inoculações com amostra de Toxoplasma gondii de origem humana em anfíbios, como as de mascerados de SNC de rã contendo cistos em camundongos, foram negativas. As inoculações de T. gondii em anfíbios foram realizadas em temperatura ambiente que no Rio de Janeiro, na época era 30º-39ºC. Não encontramos, por outro lado, cistos no SNC de anfíbios do gênero Bufo, fato assinalado por outros autores. Realizamos algumas técnicas citoquímicas para melhor caracterização do parasito. Tendo em vista o grande número de hemoparasitos encontrados nas rãs brasileiras e as infecções múltiplas ocorrerem com freqüência, apresentamos também a incidência dêstes parasitos

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

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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.

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 ...

Acidification of the parasitophorous vacuole containing Toxoplasma gondii in the presence of hydroxyurea

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Cristiane S. Carvalho

2006-09-01

Full Text Available Toxoplasma gondii multiplies within parasitophorous vacuole that is not recognized by the primary no oxidative defense of host cells, mainly represented by the fusion with acidic organelles. Recent studies have already shown that hydroxyurea arrested the intracellular parasites leading to its destruction. In the present work we investigated the cellular mechanism involved in the destruction of intracellular Toxoplasma gondii. Fluorescent vital stains were used in order to observe possible acidification of parasitophorous vacuole-containing Toxoplasma gondii in presence of hydroxyurea. Vero cells infected with tachyzoites were treated with hydroxyurea for 12, 24 or 48 hours. Fluorescence, indicative of acidification, was observed in the parasitophorous vacuole when the cultures were incubated in presence of acridine orange. LysoTracker red was used in order to determine whether lysosomes were involved in the acidification process. An intense fluorescence was observed after 12 and 24 hours of incubation with hydroxyurea, achieving it is highly intensity after 48 hours of treatment. Ultrastructural cytochemistry for localization of the acid phosphatase lysosomal enzyme was realized. Treated infected cultures showed reaction product in vesicles fusing with vacuole or associated with intravacuolar parasites. These results suggest that fusion with lysosomes and acidification of parasitophorous vacuole leads to parasites destruction in the presence pf hydroxyurea.Toxoplasma gondii se multiplica dentro do vacúolo parasitóforo que não é reconhecido pela defesa primária não oxidativa de células hospedeiras: a fusão com organelas ácidas. Estudos anteriores mostraram que hidroxiuréia interrompeu a multiplicação dos parasitos intracelulares causando sua eliminação. No presente trabalho nós investigamos o mecanismo celular envolvido na destruição do Toxoplasma gondii intracelular. Marcadores vitais fluorescentes foram usados para observar a

Cats and Goat Whey Associated with Toxoplasma gondii Infection in Pigs

NARCIS (Netherlands)

Meerburg, B.G.; Riel, van J.W.; Cornelissen, J.B.W.J.; Kijlstra, A.; Mul, M.F.

2006-01-01

In organic livestock production systems, farm-management factors are thought to play an important role in the on-farm prevalence of Toxoplasma gondii. Serological results and the results of an HACCP analysis were combined to determine important risk factors for the prevalence of this protozoan

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

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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.

Brains and Brawn: Toxoplasma Infections of the Central Nervous System and Skeletal Muscle.

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Wohlfert, Elizabeth A; Blader, Ira J; Wilson, Emma H

2017-07-01

Toxoplasma gondii is a widespread parasitic pathogen that infects over a third of the world's population. Following an acute infection, the parasite can persist within its mammalian host as intraneuronal or intramuscular cysts. Cysts will occasionally reactivate, and - depending on the host's immune status and site of reactivation - encephalitis or myositis can develop. Because these diseases have high levels of morbidity and can be lethal, it is important to understand how Toxoplasma traffics to these tissues, how the immune response controls parasite burden and contributes to tissue damage, and what mechanisms underlie neurological and muscular pathologies that toxoplasmosis patients present with. This review aims to summarize recent important developments addressing these critical topics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Donor T cells primed on leukemia lysate-pulsed recipient APCs mediate strong graft-versus-leukemia effects across MHC barriers in full chimeras.

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Ghosh, Arnab; Koestner, Wolfgang; Hapke, Martin; Schlaphoff, Verena; Länger, Florian; Baumann, Rolf; Koenecke, Christian; Cornberg, Markus; Welte, Karl; Blazar, Bruce R; Sauer, Martin G

2009-04-30

Antigen-presenting cells (APCs) of host origin drive graft-versus-leukemia (GVL) effects but can also trigger life-threatening graft-versus-host disease (GVHD) after hematopoietic cell transplantation (HCT) across major histocompatibility complex (MHC) barriers. We show that in vitro priming of donor lymphocytes can circumvent the need of recipient-derived APCs in vivo for mediating robust GVL effects and significantly diminishes the risk of severe GVHD. In vitro, generated and expanded T cells (ETCs) mediate anti-leukemia effects only when primed on recipient-derived APCs. Loading of APCs in vitro with leukemia cell lysate, chimerism status of the recipient, and timing of adoptive transfer after HCT are important factors determining the outcome. Delayed transfer of ETCs resulted in strong GVL effects in leukemia-bearing full chimera (FC) and mixed chimera (MC) recipients, which were comparable with the GVL/GVHD rates observed after the transfer of naive donor lymphocyte infusion (DLI). Upon early transfer, GVL effects were more pronounced with ETCs but at the expense of significant GVHD. The degree of GVHD was most severe in MCs after transfer of ETCs that had been in vitro primed either on nonpulsed recipient-derived APCs or with donor-derived APCs.

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

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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.

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

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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.

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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.

Seroprevalence of Toxoplasma gondii in Western Romania.

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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.

RNG1 is a Late Marker of the Apical Polar Ring in Toxoplasma gondii

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Tran, Johnson Q.; de Leon, Jessica C.; Li, Catherine; Huynh, My-Hang; Beatty, Wandy; Morrissette, Naomi S.

2010-01-01

The asexually proliferating stages of apicomplexan parasites cause acute symptoms of diseases such as malaria, cryptosporidiosis and toxoplasmosis. These stages are characterized by the presence of two independent microtubule organizing centers (MTOCs). Centrioles are found at the poles of the intranuclear spindle. The apical polar ring (APR), a MTOC unique to apicomplexans, organizes subpellicular microtubules which impose cell shape and apical polarity on these protozoa. Here we describe the characteristics of a novel protein that localizes to the APR of Toxoplasma gondii which we have named ring-1 (RNG1). There are related RNG1 proteins in Neospora caninum and Sarcocystis neurona but no obvious homologs in Plasmodium spp., Cryptosporidium spp. or Babesia spp. RNG1 is a small, low-complexity, detergent-insoluble protein that assembles at the APR very late in the process of daughter parasite replication. We were unable to knock-out the RNG1 gene, suggesting that its gene product is essential. Tagged RNG1 lines have also allowed us to visualize the APR during growth of Toxoplasma in the microtubule-disrupting drug oryzalin. Oryzalin inhibits nuclear division and cytokinesis although Toxoplasma growth continues, and similar to earlier observations of unchecked centriole duplication in oryzalin-treated parasites, the APR continues to duplicate during aberrant parasite growth. PMID:20658557

An innovative immunosensor for ultrasensitive detection of breast cancer specific carbohydrate (CA 15-3) in unprocessed human plasma and MCF-7 breast cancer cell lysates using gold nanospear electrochemically assembled onto thiolated graphene quantum dots.

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Hasanzadeh, Mohammad; Tagi, Solmaz; Solhi, Elham; Mokhtarzadeh, Ahad; Shadjou, Nasrin; Eftekhari, Aziz; Mahboob, Soltanali

2018-04-03

The accurate quantification of the level of breast cancer specific protein CA 15-3 in serum is crucial for cancer prognosis. This work, a novel and sensitive label-free immunoassay based on gold nanospear (Au NSs) electrochemically assembled onto thiolated graphene quantum dots (CysA/GQDs) for the detection of CA 15-3 antibodies. The CysA/Au NSs/GQDs hybrid interface provides a large surface area for the effective immobilization of CA 15-3 antigens, as well as it ascertains the bioactivity and stability of immobilized CA 15-3 antigens. Field emission scanning electron microscope (FE-SEM), and EDS photoelectron spectroscopies were used to monitor the sensor fabrication. Also, cyclic voltammetry was used to quantify the extent of Au NSs' surface coverage by CA 15-3 antigens. Square wave voltammetry (SWV) was employed to investigate the immunosensor fabrication and to monitor the binding events between CA 15-3 antigens-antibodies. Under optimized experimental conditions, the immunosensor displayed good sensitivity and specificity. The CA 15-3 were detected in a concentration as low as 0.11U/mL with a linear range from 0.16-125U/mL. The high sensitivity of the immunosensor may derive from the high loading of CA 15-3 antibodies on CysA/Au NSs/GQDs hybrid interface which increases the number of binding events. The method was successfully applied assay of the CA 15-3 in unprocessed human plasma samples. Also, proposed immunosensor was applied to the assay of CA 15-3 malignant cell line lysates (human breast adenocarcinoma cell line-MCF-7). Copyright © 2018. Published by Elsevier B.V.

Elp3 and RlmN: A tale of two mitochondrial tail-anchored radical SAM enzymes in Toxoplasma gondii.

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Padgett, Leah R; Lentini, Jenna M; Holmes, Michael J; Stilger, Krista L; Fu, Dragony; Sullivan, William J

2018-01-01

Radical S-adenosylmethionine (rSAM) enzymes use a 5'-deoxyadensyl 5'-radical to methylate a wide array of diverse substrates including proteins, lipids and nucleic acids. One such enzyme, Elongator protein-3 (TgElp3), is an essential protein in Toxoplasma gondii, a protozoan parasite that can cause life-threatening opportunistic disease. Unlike Elp3 homologues which are present in all domains of life, TgElp3 localizes to the outer mitochondrial membrane (OMM) via a tail-anchored trafficking mechanism in Toxoplasma. Intriguingly, we identified a second tail-anchored rSAM domain containing protein (TgRlmN) that also localizes to the OMM. The transmembrane domain (TMD) on Toxoplasma Elp3 and RlmN homologues is required for OMM localization and has not been seen beyond the chromalveolates. Both TgElp3 and TgRlmN contain the canonical rSAM amino acid sequence motif (CxxxCxxC) necessary to form the 4Fe-4S cluster required for tRNA modifications. In E. coli, RlmN is responsible for the 2-methlyadenosine (m2A) synthesis at purine 37 in tRNA while in S. cerevisiae, Elp3 is necessary for the formation of 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U) at the wobble tRNA position. To investigate why these two rSAM enzymes localize to the mitochondrion in Toxoplasma, and whether or not TgRlmN and TgElp3 possess tRNA methyltransferase activity, a series of mutational and biochemical studies were performed. Overexpression of either TgElp3 or TgRlmN resulted in a significant parasite replication defect, but overexpression was tolerated if either the TMD or rSAM domain was mutated. Furthermore, we show the first evidence that Toxoplasma tRNAGlu contains the mcm5s2U modification, which is the putative downstream product generated by TgElp3 activity.

Seroprevalence of toxoplasma-specific antibodies in patients suspected to have active toxoplasmosis: A cross-sectional survey

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Abbas Ali Eskandarian

2014-01-01

Full Text Available Background: The aim of this study was to investigate the presence and distribution of anti-toxoplasma-specific IgM and IgG tantibodies in patients suspected to have toxoplasmosis and investigate for any association between IgM and IgG antibodies and some toxoplasmosis risk factors as well. Materials and Methods: In a comparative cross-sectional study, 70 patients suspected to had active toxoplasmosis and 30 control volunteers, who gave informed consent, entered the study. In each group, patient age, sex, signs of appearance, education level, residency status (urban / rural, occupation, frequency of toxoplasma-specific IgG and IgM antibodies, abortion history, and some risk factors (Direct cat exposure, Occupational exposure to raw meat, and Raw vegetable consumption were recorded. The enzyme-linked immunosorbent assay (ELISA kits (EUROIMMUN®, United Kingdom were used for the evaluation of anti-toxoplasma IgG and IgM antibodies according to the manufacturer›s instructions. All analyses were done using SPSS-20. Results: The frequency of toxoplasma-specific IgG and IgM antibodies like: Direct cat exposures, Occupational exposure to raw meat, and Raw vegetable consumption were not statistically significant between the two groups (P > 0.05. The history of previous abortions in women in the toxoplasmosis-suspected group was significantly higher than that in the controls (31.4% versus 6.7%; P = 0.009. Conclusion: The frequency of specific IgM and IgG antibodies in toxoplasmosis suspected in the toxoplasmosis and control groups was not statistically significant.

Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: A comparative cross-sectional study

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Tegbaru Belete

2009-10-01

Full Text Available Abstract Background Toxoplasmosis in immuno-compromised hosts manifests primarily as a life threatening condition, toxoplasmic encephalitis. However, there is scarce information about the magnitude of Toxoplasma gondii infection among HIV-infected people in Ethiopia. This study was, therefore, conducted to determine the sero-prevalence of T. gondii infection among HIV-infected and HIV-uninfected subjects. Findings Sera were collected from people with and without HIV infection for the purpose of studying hepatitis B virus (HBV at St. Paul Hospital, Addis Ababa, Ethiopia from 24 January 2007 to 15 February 2007. Among these sera, the first 330 consecutive sera, 165 from each HIV sero-group, were selected and tested for anti-T. gondii IgG antibodies using Enzyme Linked Immunosorbent Assay. The seroprevalence of Toxoplasma infection was assessed against socio-demographic characteristics, HIV and HBV serostatus and HBV-related risk factors. The overall sero-prevalence of latent T. gondii infection among the study subjects was 90.0%. Toxoplasma infection was observed with respective prevalence of 93.3% and 86.7% among HIV-infected and HIV-uninfected people. Though Toxoplasma infection seems to be influenced by age, gender and HIV serostatus, only HBV serostatus was significantly associated (OR 2.71, CI 1.12 to 6.57 in multivariate logistic regression analysis. Conclusion The seroprevalence of latent T. gondii infection is high and similar by HIV status. Educating people to prevent acquisition of new Toxoplasma infection and minimizing the risk of disease manifestations among HIV-Toxoplasma co-infected individuals is important.

A contribution to the study of pyrogenic substances in radiopharmaceutical preparations. Comparison between methods using Rabbit and those using Limulus amebocytes lysate

International Nuclear Information System (INIS)

Bruneau, Jacky.

1982-10-01

We have studied two methods for pyrogenic substances detection. We used: the hyperthermic action of these substances after injection in Rabbit, and the gelation reaction of a Limulus amebocytes lysate. To apply these two methods of pyrogenic substances detection to the radiopharmaceutical preparations, we have conceived and designed a material allowing their handling in compliance with the radioactive safety norms. We have compared the sensitivity, reliability and reproducibility of these methods, one based on gelation of Limulus amebocytes lysate in presence of endotoxins, the other on the hyperthermic action of these same endotoxins in the rabbit when injected intravenously or through the suboccipital route. The discussion of the results obtained, shows that the method using the Limulus amebocytes lysate is more sensitive, less expansive and less dangerous. This method particulary well adapted to the control of radiopharmaceutical preparations, brings an additional security to the patients for whom these products are destined [fr

A new human IgG avidity test, using mixtures of recombinant antigens (rROP1, rSAG2, rGRA6), for the diagnosis of difficult-to-identify phases of toxoplasmosis.

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Drapała, Dorota; Holec-Gąsior, Lucyna; Kur, Józef; Ferra, Bartłomiej; Hiszczyńska-Sawicka, Elżbieta; Lautenbach, Dariusz

2014-07-01

The preliminary diagnostic utility of two mixtures of Toxoplasma gondii recombinant antigens (rROP1+rSAG2 and rROP1+rGRA6) in IgG ELISA and IgG avidity test has been evaluated. A total of 173 serum samples from patients with toxoplasmosis and seronegative people were examined. The sensitivity of IgG ELISA for rROP1+rSAG2 and rROP1+rGRA6 was 91.1% and 76.7%, respectively, while the reactivity for sera from patients where acute toxoplasmosis was suspected was higher, at 100% and 95.4%, respectively, than for people with chronic infection, at 88.2% and 70.6%. In this study a different trend in avidity maturation of IgG antibodies for two mixtures of proteins in comparison with native antigen was observed. The results suggest that a new IgG avidity test using the mixtures of recombinant antigens may be useful for the diagnosis of difficult-to-identify phases of toxoplasmosis. For this reason, selected mixtures after the additional tests on groups of sera with well-defined dates of infection could be used as a better alternative to the native antigens of the parasite in the serodiagnosis of human T. gondii infection. Copyright © 2014 Elsevier Inc. All rights reserved.

Evidence for a structural role for acid-fast lipids in oocyst walls of Cryptosporidium, Toxoplasma, and Eimeria.

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Bushkin, G Guy; Motari, Edwin; Carpentieri, Andrea; Dubey, Jitender P; Costello, Catherine E; Robbins, Phillips W; Samuelson, John

2013-09-03

Coccidia are protozoan parasites that cause significant human disease and are of major agricultural importance. Cryptosporidium spp. cause diarrhea in humans and animals, while Toxoplasma causes disseminated infections in fetuses and untreated AIDS patients. Eimeria is a major pathogen of commercial chickens. Oocysts, which are the infectious form of Cryptosporidium and Eimeria and one of two infectious forms of Toxoplasma (the other is tissue cysts in undercooked meat), have a multilayered wall. Recently we showed that the inner layer of the oocyst walls of Toxoplasma and Eimeria is a porous scaffold of fibers of β-1,3-glucan, which are also present in fungal walls but are absent from Cryptosporidium oocyst walls. Here we present evidence for a structural role for lipids in the oocyst walls of Cryptosporidium, Toxoplasma, and Eimeria. Briefly, oocyst walls of each organism label with acid-fast stains that bind to lipids in the walls of mycobacteria. Polyketide synthases similar to those that make mycobacterial wall lipids are abundant in oocysts of Toxoplasma and Eimeria and are predicted in Cryptosporidium. The outer layer of oocyst wall of Eimeria and the entire oocyst wall of Cryptosporidium are dissolved by organic solvents. Oocyst wall lipids are complex mixtures of triglycerides, some of which contain polyhydroxy fatty acyl chains like those present in plant cutin or elongated fatty acyl chains like mycolic acids. We propose a two-layered model of the oocyst wall (glucan and acid-fast lipids) that resembles the two-layered walls of mycobacteria (peptidoglycan and acid-fast lipids) and plants (cellulose and cutin). Oocysts, which are essential for the fecal-oral spread of coccidia, have a wall that is thought responsible for their survival in the environment and for their transit through the stomach and small intestine. While oocyst walls of Toxoplasma and Eimeria are strengthened by a porous scaffold of fibrils of β-1,3-glucan and by proteins cross

GLT-1-Dependent Disruption of CNS Glutamate Homeostasis and Neuronal Function by the Protozoan Parasite Toxoplasma gondii.

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Clément N David

2016-06-01

Full Text Available The immune privileged nature of the CNS can make it vulnerable to chronic and latent infections. Little is known about the effects of lifelong brain infections, and thus inflammation, on the neurological health of the host. Toxoplasma gondii is a parasite that can infect any mammalian nucleated cell with average worldwide seroprevalence rates of 30%. Infection by Toxoplasma is characterized by the lifelong presence of parasitic cysts within neurons in the brain, requiring a competent immune system to prevent parasite reactivation and encephalitis. In the immunocompetent individual, Toxoplasma infection is largely asymptomatic, however many recent studies suggest a strong correlation with certain neurodegenerative and psychiatric disorders. Here, we demonstrate a significant reduction in the primary astrocytic glutamate transporter, GLT-1, following infection with Toxoplasma. Using microdialysis of the murine frontal cortex over the course of infection, a significant increase in extracellular concentrations of glutamate is observed. Consistent with glutamate dysregulation, analysis of neurons reveal changes in morphology including a reduction in dendritic spines, VGlut1 and NeuN immunoreactivity. Furthermore, behavioral testing and EEG recordings point to significant changes in neuronal output. Finally, these changes in neuronal connectivity are dependent on infection-induced downregulation of GLT-1 as treatment with the ß-lactam antibiotic ceftriaxone, rescues extracellular glutamate concentrations, neuronal pathology and function. Altogether, these data demonstrate that following an infection with T. gondii, the delicate regulation of glutamate by astrocytes is disrupted and accounts for a range of deficits observed in chronic infection.

Uptake and transmission of Toxoplasma gondii oocysts by migratory filter-feeding fish

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Toxoplasma gondii is a ubiquitous parasitic protozoan known to cause disease and death in warm-blooded animals. Bottlenose dolphins, walruses, sea otters, and other marine animals worldwide have died from toxoplasmosis, but the source of this parasite in the marine environment h...

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

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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...

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 ...

Response of white mice to inoculation of irradiated organisms of the Toxoplasma strain RH

International Nuclear Information System (INIS)

Mas Bakal, P.; Veld, N. in't

1979-01-01

Chemoterapeutic agents available for use against toxoplasmosis are usually not suitable for prophylatic purposes because of their toxicity. The observed increasing number of activated latent infections with Toxoplasma, especially in immune suppressed patients, requires that safe techniques are available for use during the patients' regression period. Pretreatment of mice with Toxoplasma killed by irradiation appeared to induce resistance to challenge with virulent organisms. Survival times of six months have been observed to date. Increasing effectiveness was seen after more than one administration. Further investigation into the duration of effective resistance is needed; the question of at which intervals subsequent inoculations should be performed in order to acquire a booster effect, if any, has still to be solved before application to man can be recommended. (orig.) [de

Datation de l'infection a Toxoplasma gondii chez 128 femmes ...

African Journals Online (AJOL)

L'utilisation de ce test dans les laboratoires de biologie médicale au Togo pourrait contribuer à améliorer la prise charge adéquate des femmes enceintes au Togo. Mots clés: Toxoplasmose, sérologie, test d'avidité, femmes enceintes, Togo. English Title: Datation of Toxoplasma gondii infection among pregnant women in a ...

Environmental Exposures Are Important Risk Factors for Infection Toxoplasma gondii and Helicobacter pylori

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Background: An estimated 70% of Americans suffer chronic infections. Helicobacter pylori and Toxoplasma gondii affect an estimated 35% and 15% of Americans, respectively. Despite their heavy burden, environmental transmission of these infections is not well understood. Object...

Epidemiology of Toxoplasma and CMV serology and of GBS colonization in pregnancy and neonatal outcome in a Sicilian population.

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Puccio, Giuseppe; Cajozzo, Cinzia; Canduscio, Laura Antonella; Cino, Lucia; Romano, Amelia; Schimmenti, Maria Gabriella; Giuffrè, Mario; Corsello, Giovanni

2014-02-22

Aim of our study is to analyze the immunological status in pregnancy for two main TORCH agents, Toxoplasma and Cytomegalovirus (CMV), and the results of group B streptococcus (GBS) screening, assessing the risk for congenital infection in a population from Palermo, Italy. We retrospectively analyzed the medical records of all inborn live newborns who were born in our division during 2012, gathering information about the mother, the pregnancy and neonatal hospitalization at birth. Whenever data were available, we categorized the serologic status of the mothers for Toxoplasma and CMV. We also considered the results of rectal and vaginal swabs for GBS. We compared the results in Italian and immigrant mothers. The neonatal outcome was evaluated in all cases at risk. Prevalence of anti-Toxo IgG antibodies was 17.97%, and was significantly higher in immigrant women (30% vs 16.4% in Italian women; p = 0.0008). Prevalence of anti-CMV IgG antibodies was 65.87%. Again, it was significantly higher in immigrant women (91.4% vs 62.5%, p = 3.31e-08). We compared those data with a previous study performed in our hospital in 2005-2006, and found that the prevalence of anti-Toxoplasma and anti-CMV antibodies in our population has remained stable, both in the immigrant and in the local population. Seroconversion rates and neonatal infections were rare: no seroconversions were observed for Toxoplasma, 4 seroconversions for CMV. One neonatal Toxoplasma infection and two neonatal CMV infections were documented. In some cases with dubious patterns or probable persistence of IgM, we performed additional tests and follow-up. Vaginal and rectal swabs were positive for GBS in 7.98% of cases, with no significant difference between the Italian and the immigrant population. No GBS neonatal sepsis was documented. The prevalence of Toxoplasma IgG antibodies in pregnant women was low in our population, if compared with European countries and with other parts of Italy, and is significantly

Measuring O-GlcNAc cleavage by OGA and cell lysates on a peptide microarray.

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Sharif, Suhela; Shi, Jie; Bourakba, Mostafa; Ruijtenbeek, Rob; Pieters, Roland J

2017-09-01

O-GlcNAcylation is a post-translational modification resulting from the addition of an N-acetylglucosamine moiety to the hydroxyl groups of serine and threonine residues of nuclear and cytoplasmic proteins. In addition, O-GlcNAcylated proteins can be phosphorylated, which suggests the possibility for crosstalk between O-GlcNAcylation and phosphorylation. Dysregulation of O-GlcNAcylation affects cell signaling, transcriptional regulation, cell cycle control and can e.g. lead to tumorigenesis and tumor metastasis. There is a strong demand for efficient analytical techniques to better detect and investigate this abundant modification and its role in cancer. Herein we demonstrated the utility of an O-GlcNAcylated peptide array to examine O-GlcNAcase (OGA) activity and substrate specificity of both purified protein as well cell lysates of different cancer cell lines. Using this microarray, we clearly observed OGA activity and also inhibition thereof by OGA inhibitor thiamet G. Interestingly, different levels of OGA activity were observed of lysates derived from different cancer cell lines. This suggests that the tool may be useful in cancer research and biomarker development. Copyright © 2017 Elsevier Inc. All rights reserved.

Crioconservación de toxoplasma gondii

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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.

Viability and infectivity analysis of Toxoplasma gondii under axenic conditions = Análise da viabilidade e infectividade de taquizoítas de Toxoplasma gondii em condições axênicas

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Ferreira-da-Silva, Marialice Fonseca

2010-01-01

Conclusões: nossos dados abrem novas perspectivas para o estudo de diferentes aspectos da biologia do Toxoplasma gondii, incluindo mecanismos de nutrição, ensaios experimentais de drogas in vitro, ou estudos da biologia celular e molecular diretamente sobre o parasito

Genotyping of Toxoplasma Gondii Isolates from Soil Samples in Tehran, Iran

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M Tavalla

2013-06-01

Full Text Available Background: The protozoan parasite Toxoplasma gondii can infect any warm blooded nucleated cells. One of the ways for human infection is ingestion of oocysts directly from soil or via infected fruits or vegetables. To survey the potential role of T. gondii oocyst in soil samples, the present study was conducted in Tehran City, Iran.Methods: A total of 150 soil samples were collected around rubbish dumps, children's play ground, parks and public places. Oocysts recovery was performed by sodium nitrate flotation method on soil samples. For molecular detection, PCR reaction targeting B1 gene was performed and then, the posi­tive results were confirmed using repetitive 529 bp DNA fragment in other PCR reaction. Finally, the positive samples were genotyped at the SAG2 locus.Results: Toxoplasma DNA was found in 13 soil samples. After genotyping and RFLP analysis in SAG2 locus, nine positive samples were revealed type III, one positive sample was type I whereas three samples revealed mixed infection (type, I & III.Conclusion: The predominant genotype in Tehran soil samples is type III.

Matrix Metalloproteinase-2, Squamous Cell Carcinoma Antigen, and Tissue Polypeptide-Specific Antigen Expression in Egyptian Patients with Cervical Carcinoma: Relationship with Prognosis

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Maha Imam Ahmed

2004-01-01

Full Text Available Matrix metalloproteinases (MMPs, a family of proteolytic enzymes produced by both stromal and tumor cells, appear to have a key role in the events leading to local invasion and metastasis by malignant neoplasms. In the present study, we evaluated the role of MMP-2, squamous cell carcinoma antigen (SCCA, and tissue polypeptide – specific antigen (TPS in cervical neoplasia. Using Western blotting and enzyme immunoassay (EIA, we analyzed 50 patients with cervical carcinoma (CC and 25 normal controls for expression of MMP-2 in tissue cell lysates. We also quantified SCCA and TPS with microparticle immunoassay and EIA, respectively. The results were correlated with human papilloma virus (HPV infection, clinicopathological findings, and disease outcome. The cutoff point for each marker was estimated from receiver operating characteristic curves. Logistic regression analysis was performed to estimate the odds ratio (OR and 95% confidence interval (CI for each marker. MMP-2, SCCA, and TPS protein expression were significantly higher in patients with CC than in normal controls. While TPS was the best marker for discriminating between patients and controls, MMP-2 was associated with an advanced tumor stage (OR, 13.9 [95% CI, 1.4-133.9] and poor histological grade (OR, 10.2 [95% CI, 1.7-60.5]. Moreover, independent of the effect of an advanced CC stage and grade, the patients' age, and the presence of HPV infection, MMP-2 was considered a strong predictor for CC recurrence (OR, 8.1 [95% CI, 1.3- 49.1]. Tissue markers may be used to select high-risk patients for early detection of and adjuvant therapy for recurrence. Our MMP-2 findings are particularly relevant to the development of protease inhibitors as a new cancer therapy approach.

Vaccination of B-CLL patients with autologous dendritic cells can change the frequency of leukemia antigen-specific CD8+ T cells as well as CD4+CD25+FoxP3+ regulatory T cells toward an antileukemia response.

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Hus, I; Schmitt, M; Tabarkiewicz, J; Radej, S; Wojas, K; Bojarska-Junak, A; Schmitt, A; Giannopoulos, K; Dmoszyńska, A; Roliński, J

2008-05-01

Recently, we described that vaccination with allogeneic dendritic cells (DCs) pulsed with tumor cell lysate generated specific CD8+ T cell response in patients with B-cell chronic lymphocytic leukemia (B-CLL). In the present study, the potential of autologous DCs pulsed ex vivo with tumor cell lysates to stimulate antitumor immunity in patients with B-CLL in early stages was evaluated. Twelve patients at clinical stage 0-2 as per Rai were vaccinated intradermally up to eight times with a mean number of 7.4 x 10(6) DCs pulsed with B-CLL cell lysate. We observed a decrease of peripheral blood leukocytes and CD19+/CD5+ leukemic cells in five patients, three patients showed a stable disease and four patients progressed despite DC vaccination. A significant increase of specific cytotoxic CD8+ T lymphocytes against the leukemia-associated antigens RHAMM or fibromodulin was detected in four patients after DC vaccination. In patients with a clinical response, an increase of interleukin 12 (IL-12) serum levels and a decrease of the frequency of CD4+CD25(+)FOXP3+ T regulatory cells were observed. Taken together, the study demonstrated that vaccination with autologous DC in CLL patients is feasible and safe. Immunological and to some extend hematological responses could be noted, justifying further investigation on this immunotherapeutical approach.

Platelet lysate 3D scaffold supports mesenchymal stem cell chondrogenesis: an improved approach in cartilage tissue engineering.

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Moroz, Andrei; Bittencourt, Renata Aparecida Camargo; Almeida, Renan Padron; Felisbino, Sérgio Luis; Deffune, Elenice

2013-01-01

Articular lesions are still a major challenge in orthopedics because of cartilage's poor healing properties. A major improvement in therapeutics was the development of autologous chondrocytes implantation (ACI), a biotechnology-derived technique that delivers healthy autologous chondrocytes after in vitro expansion. To obtain cartilage-like tissue, 3D scaffolds are essential to maintain chondrocyte differentiated status. Currently, bioactive 3D scaffolds are promising as they can deliver growth factors, cytokines, and hormones to the cells, giving them a boost to attach, proliferate, induce protein synthesis, and differentiate. Using mesenchymal stem cells (MSCs) differentiated into chondrocytes, one can avoid cartilage harvesting. Thus, we investigated the potential use of a platelet-lysate-based 3D bioactive scaffold to support chondrogenic differentiation and maintenance of MSCs. The MSCs from adult rabbit bone marrow (n = 5) were cultivated and characterized using three antibodies by flow cytometry. MSCs (1 × 10(5)) were than encapsulated inside 60 µl of a rabbit platelet-lysate clot scaffold and maintained in Dulbecco's Modified Eagle Medium Nutrient Mixture F-12 supplemented with chondrogenic inductors. After 21 days, the MSCs-seeded scaffolds were processed for histological analysis and stained with toluidine blue. This scaffold was able to maintain round-shaped cells, typical chondrocyte metachromatic extracellular matrix deposition, and isogenous group formation. Cells accumulated inside lacunae and cytoplasm lipid droplets were other observed typical chondrocyte features. In conclusion, the usage of a platelet-lysate bioactive scaffold, associated with a suitable chondrogenic culture medium, supports MSCs chondrogenesis. As such, it offers an alternative tool for cartilage engineering research and ACI.

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

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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 ...

Serological Evidence of Toxoplasma gondii infection in five species of bats in China

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Toxoplasma gondii is an obligate intracellular protozoan parasite which can infect almost all warm-blooded animals and humans with a worldwide distribution. Bats are reservoirs for an increasing number of emerging zoonotic viruses, such as henipaviruses and severe acute respiratory syndrome (SARS) c...

Accuracy of real-time polymerase chain reaction for Toxoplasma gondii in amniotic fluid.

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Wallon, Martine; Franck, Jacqueline; Thulliez, Philippe; Huissoud, Cyril; Peyron, François; Garcia-Meric, Patricia; Kieffer, François

2010-04-01

To provide clinicians with information about the accuracy of real-time polymerase chain reaction (PCR) analysis of amniotic fluid for the prenatal diagnosis of congenital Toxoplasma infection. This was a prospective cohort study of women with Toxoplasma infection identified by prenatal screening in three centers routinely carrying out real-time PCR for the detection of Toxoplasma gondii in amniotic fluid. The data available were gestational age at maternal infection, types and dates of maternal treatment, results of amniocentesis and neonatal work-up and definitive infectious status of the child. We estimated sensitivity, specificity and positive and negative predictive values both overall and per trimester of pregnancy at the time of maternal infection. Polymerase chain reaction analysis was carried out on amniotic fluid for 261 of the 377 patients included (69%). It was accurate with the exception of four negative results in children who were infected. Overall sensitivity and negative predictive value were 92.2% (95% confidence interval [CI] 81-98%) and 98.1% (95% CI 95-99.5%), respectively. There was no significant association with the trimester of pregnancy during which maternal infection occurred. Specificity and positive predictive values of 100% were obtained for all trimesters. Real-time PCR analysis significantly improves the detection of T. gondii on amniotic fluid. It provides an accurate tool to predict fetal infection and to decide on appropriate treatment and surveillance. However, postnatal follow-up remains necessary in the first year of life to fully exclude infection in children for whom PCR results were negative. III.

Seroepidemiology of infection with Toxoplasma gondii in migrant agricultural workers living in poverty in Durango, Mexico.

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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.

Seroprevalence of Toxoplasma gondii and concurrent Bartonella spp., feline immunodeficiency virus, feline leukemia virus, and Dirofilaria immitis infections in Egyptian cats.

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Al-Kappany, Y M; Lappin, M R; Kwok, O C H; Abu-Elwafa, S A; Hilali, M; Dubey, J P

2011-04-01

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLv) are related to human immunodeficiency virus and human leukemia virus, respectively, and these viruses are immunosuppressive. In the present study, the prevalence of antibodies to T. gondii , Bartonella spp., FIV, as well as FeLv and Dirofilaria immitis antigens was determined in sera from feral cats (Felis catus) from Cairo, Egypt. Using a modified agglutination test, antibodies to T. gondii were found in 172 (95.5%) of the 180 cats with titers of 1∶5 in 9, 1∶10 in 9, 1∶20 in 3, 1∶40 in 5, 1∶80 in 5, 1∶160 in 15, 1∶320 in 22, and 1∶640 or higher in 104. Thus, 57.4% had high T. gondii titers. Antibodies to Bartonella spp. were found in 105 (59.6%) of 178, with titers of 1∶64 in 45, 1∶128 in 39, 1∶256 in 13, 1∶512 in 3, 1∶1,024 in 4, and 1∶2,048 in 1 cat. Antibodies to FIV were detected in 59 (33.9%) of 174 cats. Of 174 cats tested, antigens to FeLv, and D. immitis were detected in 8 (4.6%) and 6 (3.4%) cats, respectively. The results indicate a high prevalence of T. gondii, Bartonella spp., and FIV infections in cats from Cairo, Egypt. This is the first report of Bartonella spp., and D. immitis infection in cats in Egypt.

Carcinoma-associated antigens

International Nuclear Information System (INIS)

Bartorelli, A.; Accinni, R.

1981-01-01

This invention relates to novel antigens associated with breast carcinoma, anti-sera specific to said antigens, 125 I-labeled forms of said antigens and methods of detecting said antigens in serum or plasma. The invention also relates to a diagnostic kit containing standardised antigens or antisera or marked forms thereof for the detection of said antigens in human blood, serum or plasma. (author)

Antibodies to Toxoplasma gondii and Leishmania spp. in domestic cats from Luanda, Angola

Science.gov (United States)

Toxoplasma gondii and Leishmania spp. are zoonotic agents of importance to public health, with domestic cats as potential reservoirs for both protozoal infections. The present study aimed at assessing for the first time the seroprevalence of these zoonotic parasites in a domestic feline population l...

Prevalence of Toxoplasma gondii and HIV infection among pregnant women in Ibadan North Local Government, Oyo State.

Science.gov (United States)

Awobode, H O; Olubi, I C

2014-12-01

Toxoplasmosis, a disease caused by Toxoplasma gondii poses a risk of congenital infection during pregnancy in infected women. The disease poses a threat of ocular and neurological sequelae in congenitally ilfected infants and HIV patients; however, there is little valuable information on its prevalence in Ibadan. A cross sectional study of pregnant women attending antenatal care in three primary healthcare centres in Ibadan was carried out. 179 women were screened for T gondii infection using PCR, 83 of these were also screened for HIV. Forty nine (27.4%) were positive for T gondii, and 2(2.4%) were HIV positive (P = 0.002, OR = 0.28, CL = 95%). 27 (15.1%) of the infected women were in third trimester, with 20 (11.2%) and 2 (1.1%) in second and first trimester respectively. 18 (10.1%) positive cases were identified among the primigravidas and 31 (17.2%) among the multigravidas. Risk factors associated with Toxoplasma infection were assessed, and the source of drinking water and the types of animals around habitation were found to be significantly associated with the presence of Toxoplasma infection (P = 0.002, OR = 2.109 and P = 0.004, OR = 1.693 respectively). The high prevalence among women in third trimester may indicate high risk of congenital infection, and the significant association found between the source of drinking water and infection suggests environmental contamination as a major possible mode of infection. The need to educate pregnant women about the transmission mechanisms of T. gondii, and the effects of the infection on neonates and babies is pertinent in order to effectively control Toxoplasma infection.

Immunity to tumour antigens.

Science.gov (United States)

Li, Geng; Ali, Selman A; McArdle, Stephanie E B; Mian, Shahid; Ahmad, Murrium; Miles, Amanda; Rees, Robert C

2005-01-01

During the last decade, a large number of human tumour antigens have been identified. These antigens are classified as tumour-specific shared antigens, tissue-specific differentiation antigens, overexpressed antigens, tumour antigens resulting from mutations, viral antigens and fusion proteins. Antigens recognised by effectors of immune system are potential targets for antigen-specific cancer immunotherapy. However, most tumour antigens are self-proteins and are generally of low immunogenicity and the immune response elicited towards these tumour antigens is not always effective. Strategies to induce and enhance the tumour antigen-specific response are needed. This review will summarise the approaches to discovery of tumour antigens, the current status of tumour antigens, and their potential application to cancer treatment.

Isolation of Toxoplasma gondii in a pig from a local abattoir in ...

African Journals Online (AJOL)

Inoculation of pepsin digested muscle (mixed heart and diaphragm) from a slaughter pig into six Balb C mice resulted in the isolation of Toxoplasma gondii which proved to be pathogenic to mice. These infected mice were retarded in growth when compared to the two uninoculated control animals. Mouse No.3 and Mouse ...

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.

The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study

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Antonio M. Fea

2016-01-01

Full Text Available Purpose. To determine the effectiveness of autologous platelet lysate (APL eye drops in patients with primary Sjögren syndrome (SS dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM. Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI, best corrected visual acuity (BCVA, Schirmer test, fluorescein score, and breakup time (BUT. A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n=20 patients mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n=10 patients. The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p<0.05. Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications.

The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study.

Science.gov (United States)

Fea, Antonio M; Aragno, Vittoria; Testa, Valeria; Machetta, Federica; Parisi, Simone; D'Antico, Sergio; Spinetta, Roberta; Fusaro, Enrico; Grignolo, Federico M

2016-01-01

Purpose. To determine the effectiveness of autologous platelet lysate (APL) eye drops in patients with primary Sjögren syndrome (SS) dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM). Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI), best corrected visual acuity (BCVA), Schirmer test, fluorescein score, and breakup time (BUT). A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n = 20 patients) mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n = 10 patients). The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p < 0.05). Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications.

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

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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.

Detection of Toxoplasma gondii oocysts in different water resources by Loop Mediated Isothermal Amplification (LAMP).

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Gallas-Lindemann, Carmen; Sotiriadou, Isaia; Mahmoodi, Mohammad Reza; Karanis, Panagiotis

2013-02-01

Human toxoplasmosis is potentially contracted due to consumption of contaminated drinking water and represents an increasing public health risk worldwide. Toxoplasma gondii oocysts can be resistant to standard disinfection processes, including UV radiation. Increased awareness of the risk of waterborne toxoplasmosis outbreaks has led to an increase in research interest in the detection of oocysts in environmental water systems. Ninety-five environmental water samples from the Lower Rhine area in Germany have been included in the study and examined for the presence of Toxoplasma. Water samples were filtered or flocculated by aluminum sulfate and purified by sucrose density gradient. DNA was then extracted, and the DNA samples were then examined by LAMP analysis. T. gondii DNA was detected in eight out of 83 (9.6%) influent and effluent samples obtained from wastewater treatment plants. All samples (n=12) from the surface, ground, raw and tap waters tested negative. The purpose of this work was to investigate the occurrence and distribution of Toxoplasma oocysts on the Lower Rhine in Germany. Our study provides evidence that the assay is a sensitive, specific, rapid and cost effective method for the detection of T. gondii and is useful for both the investigations of cases of waterborne outbreaks and for identifying the source of contamination. Copyright © 2012 Elsevier B.V. All rights reserved.

Optimization of dipeptidic inhibitors of cathepsin L for improved Toxoplasma gondii selectivity and CNS permeability.

Science.gov (United States)

Zwicker, Jeffery D; Diaz, Nicolas A; Guerra, Alfredo J; Kirchhoff, Paul D; Wen, Bo; Sun, Duxin; Carruthers, Vern B; Larsen, Scott D

2018-06-01

The neurotropic protozoan Toxoplasma gondii is the second leading cause of death due to foodborne illness in the US, and has been designated as one of five neglected parasitic infections by the Center for Disease Control and Prevention. Currently, no treatment options exist for the chronic dormant-phase Toxoplasma infection in the central nervous system (CNS). T. gondii cathepsin L (TgCPL) has recently been implicated as a novel viable target for the treatment of chronic toxoplasmosis. In this study, we report the first body of SAR work aimed at developing potent inhibitors of TgCPL with selectivity vs the human cathepsin L. Starting from a known inhibitor of human cathepsin L, and guided by structure-based design, we were able to modulate the selectivity for Toxoplasma vs human CPL by nearly 50-fold while modifying physiochemical properties to be more favorable for metabolic stability and CNS penetrance. The overall potency of our inhibitors towards TgCPL was improved from 2 μM to as low as 110 nM and we successfully demonstrated that an optimized analog 18b is capable of crossing the BBB (0.5 brain/plasma). This work is an important first step toward development of a CNS-penetrant probe to validate TgCPL as a feasible target for the treatment of chronic toxoplasmosis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Loss of predator aversion in female rats after Toxoplasma gondii infection is not dependent on ovarian steroids.

Science.gov (United States)

Abdulai-Saiku, Samira; Vyas, Ajai

2017-10-01

Toxoplasma gondii infection reduces aversion to cat odors in male rats. Relevant proximate mechanisms include interaction of gonadal testosterone and brain nonapeptide arginine-vasopressin. Both of these substrates are sexually dimorphic with preferential expression in males; suggesting either absence of behavioral change in females or mediation by analogous neuroendocrine substrates. Here we demonstrate that Toxoplasma gondii infection reduces aversion to cat odor in female rats. This change is not accompanied by altered steroid hormones; cannot be rescued by gonadal removal; and, does not depend on arginine-vasopressin. Thus behavioral change in males and female occur through non-analogous mechanisms that remain hitherto unknown. Copyright © 2017 Elsevier Inc. All rights reserved.

The roles of cats and dogs in the transmission of Toxoplasma infection in Kuna and Embera children in eastern Panama El papel de los perros y gatos en la transmisión de la infección por Toxoplasma en niños kunas y emberas del este de Panamá

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Gina D. Etheredge

2004-09-01

Full Text Available OBJECTIVE: To examine the relationship between antibody status and various hypothesized risk factors for Toxoplasma gondiiinfection among two different Amerindian populations in eastern Panama. Following up on earlier research that we conducted, we now explore the role of dogs in the natural transmission of Toxoplasma,the role that dogs play in promoting transmission, the interactive effect of cats and dogs, and the accessibility of infective material to children. METHODS: In 1991, 10 Panamanian medical students conducted interviews and took blood samples from 760 Kuna and Embera children aged 2 through 12 years in the Upper Bayano River Basin and the San Blas Islands. Serologic assays were performed using direct agglutination. The data analyses in the 1990s included univariate, bivariate, and multivariate analyses, without regard to data on dogs. Further bivariate and multivariate analyses were performed in 2003 to examine the contribution of dogs. RESULTS: In communities with high Toxoplasmaantibody prevalence in children, logistic regression suggested that the factors predictive of antibody presence were: compacted soil floors of huts (P= 0.001, having a dog (P= 0.038, and the interviewer seeing a cat in the house (P= 0.049. Our results suggest that the villagers' dogs play a significant role in facilitating the transmission of Toxoplasma gondiito humans, most often in the presence of cats in the houses, and only in those communities with higher Toxoplasmas eroprevalence in children. CONCLUSIONS: Dogs may act as mechanical vectors, by rolling in foul-smelling substances and by ingesting fecal material. In areas of high Toxoplasma prevalence in children and where dogs and cats are plentiful, immunocompromised individuals and pregnant women should be warned of the possibility of acquiring Toxoplasma gondii from dogs as well as from soil contaminated by cats. People should be encouraged to wash their hands after contact with soil, dogs, or cats

Activation of NO and cytokines by low-molecular weight fractions of lysates from G+ and G bacteria

Czech Academy of Sciences Publication Activity Database

Kmoníčková, Eva; Dusilová, Adéla; Kostecká, Petra; Kverka, Miloslav; Zídek, Zdeněk

2013-01-01

Roč. 157, Suppl.1 (2013), S51-S55 ISSN 1213-8118 R&D Projects: GA ČR GAP303/12/0535 Institutional support: RVO:68378041 ; RVO:61388971 Keywords : bacteria * lysate * immunomodulation Subject RIV: FR - Pharmacology ; Medidal Chemistry; EC - Immunology (MBU-M) Impact factor: 1.661, year: 2013

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...

Antibodies to Toxoplasma gondii and Leishmania spp. in domestic cats from Luanda, Angola

NARCIS (Netherlands)

Lopes, Ana Patrícia; Oliveira, Ana Cristina; Granada, Sara; Rodrigues, Filipa T.; Papadopoulos, Elias; Schallig, Henk; Dubey, Jitender P.; Cardoso, Luís

2017-01-01

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

Serology and genetics of Toxoplasma gondii in endangered Hawaiian (Nene) geese (Branta sandvicensis)

Science.gov (United States)

Toxoplasma gondii is parasite transmitted by feral cats that has historically caused mortality in native Hawaiian birds. A recent study revealed that this parasite accounts for ca. 4% of causes of mortality in native Hawaiian geese (nene-Branta sandvicensis). To know how widespread exposure to the...

Toxoplasma gondii as a Risk Factor for Early-Onset Schizophrenia: Analysis of Filter Paper Blood Samples Obtained at Birth

DEFF Research Database (Denmark)

Mortensen, Preben Bo; Nørgaard-Pedersen, Bent; Waltoft, Berit Lindum

2007-01-01

BACKGROUND: Infections during fetal life or neonatal period, including infections with Toxoplasma gondii, may be associated with a risk for schizophrenia and other mental disorders. The objectives of this study were to study the association between serological markers for maternal and neonatal....... Patients included persons born in Denmark in 1981 or later followed up through 1999 with respect to inpatient or outpatient treatment for schizophrenia or related disorders (ICD-10 F2) or affective disorders (ICD-10 F3). RESULTS: Toxoplasma gondii immunoglobulin G (IgG) levels corresponding to the upper...

Toxoplasma gondii as a Risk Factor for Early-Onset Schizophrenia: Analysis of Filter Paper Blood Samples Obtained at Birth

DEFF Research Database (Denmark)

Mortensen, Preben Bo; Nørgaard-Pedersen, Bent; Waltoft, Berit Lindum

2006-01-01

BACKGROUND: Infections during fetal life or neonatal period, including infections with Toxoplasma gondii, may be associated with a risk for schizophrenia and other mental disorders. The objectives of this study were to study the association between serological markers for maternal and neonatal....... Patients included persons born in Denmark in 1981 or later followed up through 1999 with respect to inpatient or outpatient treatment for schizophrenia or related disorders (ICD-10 F2) or affective disorders (ICD-10 F3). RESULTS: Toxoplasma gondii immunoglobulin G (IgG) levels corresponding to the upper...

Evaluation of a platelet lysate bilayered system for periodontal regeneration in a rat intrabony three-wall periodontal defect

NARCIS (Netherlands)

Babo, P.S.; Cai, X; Plachokova, A.S.; Reis, R.L.; Jansen, J.A.; Gomes, M.E.; Walboomers, X.F.

2018-01-01

With currently available therapies, full regeneration of lost periodontal tissues after periodontitis cannot be achieved. In this study, a combined compartmentalized system was tested, composed of (a) a platelet lysate (PL)-based construct, which was placed along the root aiming to regenerate the

Seroprevalence of Toxoplasma gondii in the Iranian general population: a systematic review and meta-analysis.

Science.gov (United States)

Daryani, Ahmad; Sarvi, Shahabeddin; Aarabi, Mohsen; Mizani, Azadeh; Ahmadpour, Ehsan; Shokri, Azar; Rahimi, Mohammad-Taghi; Sharif, Mehdi

2014-09-01

Toxoplasma gondii is one of the most common protozoan parasites with widespread distribution globally. It is the causative agent of Toxoplasma infection, which is prevalent in human and other warm-blooded vertebrates. While T. gondii infection in healthy people is usually asymptomatic, it can lead to serious pathological effects in congenital cases and immunodeficient patients. We sought to identify the seroprevalence rate of Toxoplasma infection in the Iranian general population to develop a comprehensive description of the disease condition in Iran for future use. Electronic databases (PubMed, Google Scholar, Science Direct, and Scopus) and Persian language databases (Magiran, Scientific Information Database [SID], Iran Medex, and Iran Doc) were searched. Furthermore, graduate student dissertations and proceedings of national parasitology congresses were searched manually. Our search resulted in a total of 35 reports published from 1978 to 2012.These include 22 published articles, 1 unpublished study, 8 proceedings from the Iranian conference of parasitology, and 4 graduate student dissertations, resulting in 52,294 individuals and 23,385 IgG seropositive cases. The random errors method was used for this meta-analysis. The result shows that the overall seroprevalence rate of toxoplasmos is among the general population in Iran was 39.3% (95% CI=33.0%-45.7%). There was no significant difference in the seroprevalence rate between male and female patients. A significant linear trend of increasing overall prevalence by age was noted (P<0.0001). In addition, the data indicates that there are high seroprevalence in groups who have direct contact with cats, consume uncooked meat and raw fruits or vegetables, in farmers and Housewife, individuals who have a low level of education, and live in rural areas. To the best of our knowledge, this is the first systematic review of T. gondii infection seroprevalence in Iran, which shows a high prevalence of Toxoplasma infection

Dendritic Cells Loaded with Pancreatic Cancer Stem Cells (CSCs) Lysates Induce Antitumor Immune Killing Effect In Vitro

Science.gov (United States)

Yin, Tao; Shi, Pengfei; Gou, Shanmiao; Shen, Qiang; Wang, Chunyou

2014-01-01

According to the cancer stem cells (CSCs) theory, malignant tumors may be heterogeneous in which a small population of CSCs drive the progression of cancer. Because of their intrinsic abilities, CSCs may survive a variety of treatments and then lead to therapeutic resistance and cancer recurrence. Pancreatic CSCs have been reported to be responsible for the malignant behaviors of pancreatic cancer, including suppression of immune protection. Thus, development of immune strategies to eradicate pancreatic CSCs may be of great value for the treatment of pancreatic cancer. In this study, we enriched pancreatic CSCs by culturing Panc-1 cells under sphere-forming conditions. Panc-1 CSCs expressed low levels of HLA-ABC and CD86, as measured by flow cytometry analysis. We further found that the Panc-1 CSCs modulate immunity by inhibiting lymphocyte proliferation which is promoted by phytohemagglutinin (PHA) and anti-CD3 monoclonal antibodies. The monocyte derived dendritic cells (DCs) were charged with total lysates generated from Panc-1 CSCs obtained from tumor sphere culturing. After co-culturing with lymphocytes at different ratios, the Panc-1 CSCs lysates modified DC effectively promoted lymphocyte proliferation. The activating efficiency reached 72.4% and 74.7% at the ratios of 1∶10 and 1∶20 with lymphocytes. The activated lymphocytes secreted high levels of INF-γ and IL-2, which are strong antitumor cytokines. Moreover, Panc-1 CSCs lysates modified DC induced significant cytotoxic effects of lymphocytes on Panc-1 CSCs and parental Panc-1 cells, respectively, as shown by lactate dehydrogenase (LDH) assay. Our study demonstrates that the development of CSCs-based vaccine is a promising strategy for treating pancreatic cancer. PMID:25521461

Dendritic cells loaded with pancreatic Cancer Stem Cells (CSCs lysates induce antitumor immune killing effect in vitro.

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Tao Yin

Full Text Available According to the cancer stem cells (CSCs theory, malignant tumors may be heterogeneous in which a small population of CSCs drive the progression of cancer. Because of their intrinsic abilities, CSCs may survive a variety of treatments and then lead to therapeutic resistance and cancer recurrence. Pancreatic CSCs have been reported to be responsible for the malignant behaviors of pancreatic cancer, including suppression of immune protection. Thus, development of immune strategies to eradicate pancreatic CSCs may be of great value for the treatment of pancreatic cancer. In this study, we enriched pancreatic CSCs by culturing Panc-1 cells under sphere-forming conditions. Panc-1 CSCs expressed low levels of HLA-ABC and CD86, as measured by flow cytometry analysis. We further found that the Panc-1 CSCs modulate immunity by inhibiting lymphocyte proliferation which is promoted by phytohemagglutinin (PHA and anti-CD3 monoclonal antibodies. The monocyte derived dendritic cells (DCs were charged with total lysates generated from Panc-1 CSCs obtained from tumor sphere culturing. After co-culturing with lymphocytes at different ratios, the Panc-1 CSCs lysates modified DC effectively promoted lymphocyte proliferation. The activating efficiency reached 72.4% and 74.7% at the ratios of 1∶10 and 1∶20 with lymphocytes. The activated lymphocytes secreted high levels of INF-γ and IL-2, which are strong antitumor cytokines. Moreover, Panc-1 CSCs lysates modified DC induced significant cytotoxic effects of lymphocytes on Panc-1 CSCs and parental Panc-1 cells, respectively, as shown by lactate dehydrogenase (LDH assay. Our study demonstrates that the development of CSCs-based vaccine is a promising strategy for treating pancreatic cancer.

Veterinary vaccines against Toxoplasma gondii

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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.

Tunisian Toxoplasma gondii strains genotyping by the use of AK69 marker

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Aoun Karim

2011-08-01

Full Text Available Abstract Background Clinical manifestation due to infection by Toxoplasma gondii is closely linked to the infecting strain of the parasite. Several genetic markers are available to determinate its genotype but few of them are able to discriminate between the three predominant lineages, namely types I, II and III. The number of markers decreases when atypical, recombinant/mixed genotypes need to be identified. Findings In our study, the contribution of sequence polymorphisms in the AK69 gene as typing markers for T. gondii was investigated for the first time in an epidemiological study. The coding region of the marker was amplified, sequenced and aligned for different Toxoplasma strains. The identified nucleotide polymorphism at 12 positions was able to highly discriminate between the different congenital toxoplasmosis Tunisian strains. Moreover the high detection sensitivity level of the marker enabled unambiguous identification of mixed/recombinant genotypes directly. Conclusion It can be, thus, very useful for direct typing in areas where such genotypes are frequently encountered, mainly in the African continent.

Development and validation of an antigen-binding capture ELISA for native and putrescine-modified anti-tetanus F(ab')2 fragments for the assessment of the cellular uptake and plasma kinetics of the antibodies.

Science.gov (United States)

Welfringer, Frédéric; d'Athis, Philippe; Scherrmann, Jean-Michel; Hervé, Françoise

2005-12-20

Cationization is a strategy to enhance the permeability of antibodies to physiological membranes for potential therapeutic and diagnostic applications of these proteins, with one of its crucial points being the retention of antigen binding activity. Here, we describe the cationization of horse polyclonal anti-tetanus F(ab')(2) fragments and the development and validation of an ELISA for quantitative measurements of the binding activity of the native and cationized F(ab')(2) in cell lysates and rat plasma samples, assessing the cellular uptake and plasma kinetics of these antibodies, respectively. The method used tetanus anatoxin coated on microtitre plates as capture antigen to bind sample or standard F(ab')(2), the amount of antibody binding being quantified using, first, a secondary biotinylated anti-horse antibody/streptavidin-alkaline phosphatase complex in situ and then a measurement of the substrate product. Cationization of the F(ab')(2) was performed with putrescine at pH 4.5 using soluble carbodiimide as carboxyl activator. The average substitution ratio was determined at 3 putrescine molecules per F(ab')(2) molecule. The cationized F(ab')(2) retained roughly 80% of the initial antigen binding activity and was stable over a 1 year period of storage at -20 degrees C. The ELISA validation data showed that the method was linear for both the native and cationized F(ab')(2) using Hanks' balanced saline solution with 0.2% bovine serum albumin as assay diluent for the cell lysate samples. The useful F(ab')(2) concentration range was 2.5-25 ng/ml and the limit of quantification was 2.5 ng/ml. With rat blank plasma used as assay diluent for the rat plasma samples the useful F(ab')(2) concentration range was 3.5-25 ng/ml and the limit of quantification was 3.5 ng/ml. Specific requirements for the limits of quantification were fulfilled: precision tetanus F(ab')(2) in an HL 60 cell model, and of plasma kinetics after i.v. administration to rats.

Heat inactivation of a norovirus surrogate in cell culture lysate, abalone meat, and abalone viscera.

Science.gov (United States)

Park, Shin Young; Bae, San-Cheong; Ha, Sang-Do

2015-03-01

The current study examined the effects of temperature and heat treatment duration on murine norovirus-1 (MNV-1) from both viral cell culture lysate (7-8 log10 PFU) and experimentally contaminated abalone meat and viscera (5-6 log10 PFU) as a model of human norovirus (NoV). MNV-1 titers in cell culture lysate, abalone meat, and abalone viscera were gradually reduced to 1.93-4.55, 1.79-3.00, and 2.26-3.26 log10 PFU/ml, respectively, after treatment at 70 °C for 1-10 min. Treatment at 85 °C for 1-5 min gradually reduced MNV-1 titers in abalone meat to 2.71-4.15 log10 PFU/ml. MNV-1 titers in abalone viscera were gradually reduced to 2.91-3.46 log10 PFU/ml after treatment at 85 °C for 1-3 min. No significant difference (P > 0.05) was found in MNV-1 titers in the abalone meat and viscera among treatment groups (70 °C for 5 min, 70 °C for 3 min, and 85 °C for 1 min). Complete inactivation of MNV-1 in cell culture lysate was determined at 85 °C for ≥1 min and 100 °C for ≥0.5 min. Complete inactivation of MNV-1 in abalone was determined at 100 °C for ≥0.5 min for meat, and 85 °C for 5 min and 100 °C for ≥0.5 min for viscera. At treatments at 70 °C, the Td-values (3 log reduction time) were significantly lower (P abalone meat (6.07) and viscera (10.73). Td = 3 values were not significantly different (P > 0.05) between abalone meat (1.78) and abalone viscera (1.33) at treatments at 85 °C. This study suggests that 100 °C for ≥0.5 min could potentially be used to inactivate NoV in molluscan shellfishes, including viscera.

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...

Decreased mechanical properties of heart valve tissue constructs cultured in platelet lysate as compared to fetal bovine serum

NARCIS (Netherlands)

Geemen, van D.; Riem Vis, P.W.; Soekhradj - Soechit, R.S.; Sluijter, J.P.G.; Liefde - van Beest, de M.; Kluin, J.; Bouten, C.V.C.

2011-01-01

In autologous heart valve tissue engineering, there is an ongoing search for alternatives of fetal bovine serum (FBS). Human platelet-lysate (PL) might be a promising substitute. In the present article, we aimed to examine the tissue formation, functionality, and mechanical properties of engineered

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

Research on antibodies anti toxoplasma gondii in intraocular fluids (Aqueous and vitreous humor) from patients with ocular toxoplasmosis, in the City of Belém, Pará State

OpenAIRE

Carmo, Ediclei Lima do; Almeida, Edmundo Frota; Bichara, Cléa Nazaré; Póvoa, Marinete Marins

2005-01-01

Foi realizada pesquisa de anticorpos IgG, IgM e IgA anti-Toxoplasma gondii no soro e fluidos intra-oculares (humor aquoso e vítreo) de pacientes com toxoplasmose ocular. A partir dos resultados obtidos verificou-se que anticorpos IgG e IgA intraocular anti-Toxoplasma gondii podem vir a ser importantes marcadores no diagnóstico de toxoplasmose ocular.Tests were performed for antibodies IgG, IgM and IgA anti-Toxoplasma gondii antibodies in serum and intraocular fluids (Aqueous and vitreous humo...

Risk factors for Toxoplasma gondii infection in Kohat District, Pakistan

OpenAIRE

Gul Naila; Zareen Shehzad; Ur Rehman Faiz; Ur Rehman Hameed; Qayyum Sumbel; Khan Sumiya; Khan Feroz; Ali Khan Munsif; Saeed Kausar; Ayub Abid; Hayat Azam; Ateeq Muhammad; Ahmad Waqar

2017-01-01

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 wit...

Strain-dependent augmentation of tight-junction barrier function in human primary epidermal keratinocytes by Lactobacillus and Bifidobacterium lysates.

Science.gov (United States)

Sultana, Reshma; McBain, Andrew J; O'Neill, Catherine A

2013-08-01

In this study, we investigated whether probiotic lysates can modify the tight-junction function of human primary keratinocytes. The keratinocytes were grown on cell culture inserts and treated with lysates from Bifidobacterium longum, Lactobacillus plantarum, Lactobacillus reuteri, Lactobacillus fermentum, or Lactobacillus rhamnosus GG. With the exception of L. fermentum (which decreased cell viability), all strains markedly enhanced tight-junction barrier function within 24 h, as assessed by measurements of transepithelial electrical resistance (TEER). However, B. longum and L. rhamnosus GG were the most efficacious, producing dose-dependent increases in resistance that were maintained for 4 days. These increases in TEER correlated with elevated expression of tight-junction protein components. Neutralization of Toll-like receptor 2 abolished both the increase in TEER and expression of tight-junction proteins induced by B. longum, but not L. rhamnosus GG. These data suggest that some bacterial strains increase tight-junction function via modulation of protein components but the different pathways involved may vary depending on the bacterial strain.

Toxoplasma gondii in stranded marine mammals from the North Sea and Eastern Atlantic Ocean

NARCIS (Netherlands)

Velde, van de Norbert; Devleesschauwer, Brecht; Leopold, Mardik; Begeman, Lineke; IJsseldijk, Lonneke; Hiemstra, Sjoukje; IJzer, Jooske; Brownlow, Andrew; Davison, Nicholas; Haelters, Jan

2016-01-01

The occurrence of the zoonotic protozoan parasite Toxoplasma gondii in marine mammals remains a poorly understood phenomenon. In this study, samples from 589 marine mammal species and 34 European otters (Lutra lutra), stranded on the coasts of Scotland, Belgium, France, The Netherlands and

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

NARCIS (Netherlands)

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

2015-01-01

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

Literature Reference for Toxoplasma gondii (Applied and Environmental Microbiology. 2004. 70(7): 4035–4039)

Science.gov (United States)

Procedures are described for analysis of water samples and may be adapted for assessment of solid, particulate and liquid samples. The method uses real-time PCR assay for detecting Toxoplasma gondii DNA using gene-specific primers and probe.

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.

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.

Rapid and sensitive detection of multiple microRNAs in cell lysate by low-fouling surface plasmon resonance biosensor

Czech Academy of Sciences Publication Activity Database

Vaisocherová, Hana; Šípová, Hana; Víšová, Ivana; Bocková, Markéta; Špringer, Tomáš; Ermini, Maria Laura; Chadtová Song, Xue; Krejčík, Z.; Chrastinová, L.; Pastva, O.; Pimková, K.; Merkerová-Dostálová, M.; Dyr, J. E.; Homola, Jiří

2015-01-01

Roč. 70, August 05 (2015), s. 226-231 ISSN 0956-5663 R&D Projects: GA ČR(CZ) GBP205/12/G118 Institutional support: RVO:67985882 Keywords : Erythrocyte lysate * Polymer brushes * DNA array Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 7.476, year: 2015

Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens.

OpenAIRE

Ruedl, C; Frühwirth, M; Wick, G; Wolf, H

1994-01-01

We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens. After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G [IgG], IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence. The...

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-...

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

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...

Toxoplasma gondii and Neospora caninum seroprevalence in dairy sheep and goats mixed stock farming.

Science.gov (United States)

Diakoua, Anastasia; Anastasia, Diakou; Papadopoulos, Elias; Elias, Papadopoulos; Panousis, Nikolaos; Nikolaos, Panousis; Karatzias, Charilaos; Charilaos, Karatzias; Giadinis, Nektarios; Nektarios, Giadinis

2013-12-06

Toxoplasma and Neospora infections are important causes of abortions and economic losses in animal production. Mixed stock farming of sheep and goats is a common practice in Mediterranean countries and could serve as a suitable model for the evaluation of differences between the two animal species regarding parasitic infections. In order to investigate the seroprevalence of T. gondii and N. caninum among flocks of small ruminants in Greece and to evaluate any prevalence difference between sheep and goats kept in mixed flocks, 833 sera samples (458 sheep and 375 goats) from 50 mixed flocks in different areas of the country were examined by ELISA for the detection of specific antibodies. Specific IgG against T. gondii were detected in 53.71% and 61.3% and against N. caninum in 16.8% and 6.9% of the sheep and goats, respectively. Goats had higher Toxoplasma seroprevalence than sheep (pgoats (pgoats that are kept together in mixed flocks. Copyright © 2013 Elsevier B.V. All rights reserved.

Distribution of AAV8 particles in cell lysates and culture media changes with time and is dependent on the recombinant vector

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Bryan A Piras

2016-01-01

Full Text Available With clinical trials ongoing, efficient clinical production of adeno-associated virus (AAV to treat large numbers of patients remains a challenge. We compared distribution of AAV8 packaged with Factor VIII (FVIII in cell culture media and lysates on days 3, 5, 6, and 7 post-transfection and found increasing viral production through day 6, with the proportion of viral particles in the media increasing from 76% at day 3 to 94% by day 7. Compared to FVIII, AAV8 packaged with Factor IX and Protective Protein/Cathepsin A vectors demonstrated a greater shift from lysate towards media from day 3 to 6, implying that particle distribution is dependent on recombinant vector. Larger-scale productions showed that the ratio of full-to-empty AAV particles is similar in media and lysate, and that AAV harvested on day 6 post-transfection provides equivalent function in mice compared to AAV harvested on day 3. This demonstrates that AAV8 production can be optimized by prolonging the duration of culture post-transfection, and simplified by allowing harvest of media only, with disposal of cells that contain 10% or less of total vector yield. Additionally, the difference in particle distribution with different expression cassettes implies a recombinant vector-dependent processing mechanism which should be taken into account during process development.

Fundamental Roles of the Golgi-Associated Toxoplasma Aspartyl Protease, ASP5, at the Host-Parasite Interface

Czech Academy of Sciences Publication Activity Database

Hammoudi, P.-M.; Jacot, D.; Mueller, C.; Di Cristina, M.; Dogga, S.K.; Marq, J.-B.; Romano, J.; Tosetti, N.; Dubrot, J.; Emre, Y.; Lunghi, M.; Coppens, I.; Yamamoto, M.; Sojka, Daniel; Pino, P.; Soldati-Favre, D.

2015-01-01

Roč. 11, č. 10 (2015), e1005211 E-ISSN 1553-7374 Institutional support: RVO:60077344 Keywords : Toxoplasma gondii * Plasmodium proteins * ASP5 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.003, year: 2015

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....

β-1,3-Glucan, Which Can Be Targeted by Drugs, Forms a Trabecular Scaffold in the Oocyst Walls of Toxoplasma and Eimeria

Science.gov (United States)

Bushkin, G. Guy; Motari, Edwin; Magnelli, Paula; Gubbels, Marc-Jan; Dubey, Jitender P.; Miska, Katarzyna B.; Bullitt, Esther; Costello, Catherine E.; Robbins, Phillips W.; Samuelson, John

2012-01-01

ABSTRACT The walls of infectious pathogens, which are essential for transmission, pathogenesis, and diagnosis, contain sugar polymers that are defining structural features, e.g., β-1,3-glucan and chitin in fungi, chitin in Entamoeba cysts, β-1,3-GalNAc in Giardia cysts, and peptidoglycans in bacteria. The goal here was to determine in which of three walled forms of Toxoplasma gondii (oocyst, sporocyst, or tissue cyst) is β-1,3-glucan, the product of glucan synthases and glucan hydrolases predicted by whole-genome sequences of the parasite. The three most important discoveries were as follows. (i) β-1,3-glucan is present in oocyst walls of Toxoplasma and Eimeria (a chicken parasite that is a model for intestinal stages of Toxoplasma) but is absent from sporocyst and tissue cyst walls. (ii) Fibrils of β-1,3-glucan are part of a trabecular scaffold in the inner layer of the oocyst wall, which also includes a glucan hydrolase that has a novel glucan-binding domain. (iii) Echinocandins, which target the glucan synthase and kill fungi, arrest development of the Eimeria oocyst wall and prevent release of the parasites into the intestinal lumen. In summary, β-1,3-glucan, which can be targeted by drugs, is an important component of oocyst walls of Toxoplasma but is not a component of sporocyst and tissue cyst walls. PMID:23015739

Fatal attraction phenomenon in humans: cat odour attractiveness increased for toxoplasma-infected men while decreased for infected women.

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Jaroslav Flegr

2011-11-01

Full Text Available Latent toxoplasmosis, a lifelong infection with the protozoan Toxoplasma gondii, has cumulative effects on the behaviour of hosts, including humans. The most impressive effect of toxoplasmosis is the "fatal attraction phenomenon," the conversion of innate fear of cat odour into attraction to cat odour in infected rodents. While most behavioural effects of toxoplasmosis were confirmed also in humans, neither the fatal attraction phenomenon nor any toxoplasmosis-associated changes in olfactory functions have been searched for in them.Thirty-four Toxoplasma-infected and 134 noninfected students rated the odour of urine samples from cat, horse, tiger, brown hyena and dog for intensity and pleasantness. The raters were blind to their infection status and identity of the samples. No signs of changed sensitivity of olfaction were observed. However, we found a strong, gender dependent effect of toxoplasmosis on the pleasantness attributed to cat urine odour (p = 0.0025. Infected men rated this odour as more pleasant than did the noninfected men, while infected women rated the same odour as less pleasant than did noninfected women. Toxoplasmosis did not affect how subjects rated the pleasantness of any other animal species' urine odour; however, a non-significant trend in the same directions was observed for hyena urine.The absence of the effects of toxoplasmosis on the odour pleasantness score attributed to large cats would suggest that the amino acid felinine could be responsible for the fatal attraction phenomenon. Our results also raise the possibility that the odour-specific threshold deficits observed in schizophrenia patients could be caused by increased prevalence of Toxoplasma-infected subjects in this population rather than by schizophrenia itself. The trend observed with the hyena urine sample suggests that this carnivore, and other representatives of the Feliformia suborder, should be studied for their possible role as definitive hosts in

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

Probable neuroimmunological link between Toxoplasma and cytomegalovirus infections and personality changes in the human host

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Roubalová Kateřina

2005-07-01

Full Text Available Abstract Background Recently, a negative association between Toxoplasma-infection and novelty seeking was reported. The authors suggested that changes of personality trait were caused by manipulation activity of the parasite, aimed at increasing the probability of transmission of the parasite from an intermediate to a definitive host. They also suggested that low novelty seeking indicated an increased level of the neurotransmitter dopamine in the brain of infected subjects, a phenomenon already observed in experimentally infected rodents. However, the changes in personality can also be just a byproduct of any neurotropic infection. Moreover, the association between a personality trait and the toxoplasmosis can even be caused by an independent correlation of both the probability of Toxoplasma-infection and the personality trait with the third factor, namely with the size of living place of a subject. To test these two alternative hypotheses, we studied the influence of another neurotropic pathogen, the cytomegalovirus, on the personality of infected subjects, and reanalyzed the original data after the effect of the potential confounder, the size of living place, was controlled. Methods In the case-control study, 533 conscripts were tested for toxoplasmosis and presence of anti-cytomegalovirus antibodies and their novelty seeking was examined with Cloninger's TCI questionnaire. Possible association between the two infections and TCI dimensions was analyzed. Results The decrease of novelty seeking is associated also with cytomegalovirus infection. After the size of living place was controlled, the effect of toxoplasmosis on novelty seeking increased. Significant difference in novelty seeking was observed only in the largest city, Prague. Conclusion Toxoplasma and cytomegalovirus probably induce a decrease of novelty seeking. As the cytomegalovirus spreads in population by direct contact (not by predation as with Toxoplasma, the observed changes are

A complex small RNA repertoire is generated by a plant/fungal-like machinery and effected by a metazoan-like Argonaute in the single-cell human parasite Toxoplasma gondii.

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Laurence Braun

2010-05-01

Full Text Available In RNA silencing, small RNAs produced by the RNase-III Dicer guide Argonaute-like proteins as part of RNA-induced silencing complexes (RISC to regulate gene expression transcriptionally or post-transcriptionally. Here, we have characterized the RNA silencing machinery and exhaustive small RNAome of Toxoplasma gondii, member of the Apicomplexa, a phylum of animal- and human-infecting parasites that cause extensive health and economic damages to human populations worldwide. Remarkably, the small RNA-generating machinery of Toxoplasma is phylogenetically and functionally related to that of plants and fungi, and accounts for an exceptionally diverse array of small RNAs. This array includes conspicuous populations of repeat-associated small interfering RNA (siRNA, which, as in plants, likely generate and maintain heterochromatin at DNA repeats and satellites. Toxoplasma small RNAs also include many microRNAs with clear metazoan-like features whose accumulation is sometimes extremely high and dynamic, an unexpected finding given that Toxoplasma is a unicellular protist. Both plant-like heterochromatic small RNAs and metazoan-like microRNAs bind to a single Argonaute protein, Tg-AGO. Toxoplasma miRNAs co-sediment with polyribosomes, and thus, are likely to act as translational regulators, consistent with the lack of catalytic residues in Tg-AGO. Mass spectrometric analyses of the Tg-AGO protein complex revealed a common set of virtually all known RISC components so far characterized in human and Drosophila, as well as novel proteins involved in RNA metabolism. In agreement with its loading with heterochromatic small RNAs, Tg-AGO also associates substoichiometrically with components of known chromatin-repressing complexes. Thus, a puzzling patchwork of silencing processor and effector proteins from plant, fungal and metazoan origin accounts for the production and action of an unsuspected variety of small RNAs in the single-cell parasite Toxoplasma and

Toxoplasma Infection in Schizophrenia Patients: A Comparative Study with Control Group

OpenAIRE

Alipour, A; Shojaee, S; Mohebali, M; Tehranidoost, M; Abdi Masoleh, F; Keshavarz, H

2011-01-01

Background: Schizophrenia is a serious, chronic, and often debilitating neuropsychiatric disor­der. Its causes are still poorly understood. Besides genetic and non-genetic (environmental) fac­tors are thought to be important as the cause of the structural and functional deficits that character­ize schizophrenia. This study aimed to compare Toxoplasma gondii infection between schizo­phrenia patients and non-schizophrenia individuals as control group.Methods: A case-control study was designed i...

Seroprevalence and risk factors for toxoplasma infection among pregnant women in Aydin province, Turkey.

Science.gov (United States)

Ertug, Sema; Okyay, Pinar; Turkmen, Munevver; Yuksel, Hasan

2005-06-15

The aims of the present study were to determine the prevalence of toxoplasmosis in pregnant women at first trimester of their pregnancy and to follow up the seroconversion for next two trimesters, and to identify the risk factors and possible contamination routes in Aydin province, Turkey. The sample size was calculated as 423 on a prevalence of 50%, d=0.05 at a confidence level of 95% with 10% addition. It was a cross-sectional study with multistage sampling. After a questionnaire applied to the pregnant women, anti-Toxoplasma IgG antibodies were studied with ELISA and IFA, values in conflict with DA test, where IgM antibodies were studied with ELISA and for borderline or positive values of IgM avidity test was used. The mean age of 389 (92.9%) of pregnant women in the study was 24.28+/-4.56 years, the seroprevalence of anti-Toxoplasma IgG antibodies for toxoplasmosis was 30.1%. Seroprevalence was increased with age (p=0.001) and with drinking water consumption other than bottled water (p=0.042). No significant relations were observed between anti-Toxoplasma IgG antibodies and education level, being native or migrant, abortion history, consumption of meat, vegetable and milk/milk products, personal or kitchen hygiene habits, cat owning at home of the pregnant women. No IgM antibody was detected. One of every three pregnant women in Aydin was at risk of toxoplasmosis at the first trimester of their pregnancy. Increased seroprevalance with age was a predictable result because of increasing time of exposure. Increased seroprevalence with consumption of municipal and uncontrolled water (well/spring water) supplies was similar with latest epidemiological findings.

Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

Science.gov (United States)

Aryanpour, J; Hafizi, A; Modabber, F

1980-03-01

Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG seems to be dependent upon T-cells in Toxoplasma-infected mice.

Electrospun Gelatin–Chondroitin Sulfate Scaffolds Loaded with Platelet Lysate Promote Immature Cardiomyocyte Proliferation

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Francesca Saporito

2018-02-01

Full Text Available The aim of the present work was the development of heart patches based on gelatin (G and chondroitin sulfate (CS to be used as implants to improve heart recovery after corrective surgery for critical congenital heart defects (CHD. Patches were prepared by means of electrospinning to obtain nanofibrous scaffolds and they were loaded with platelet lysate (PL as a source of growth factors to further enhance the repair process. Scaffolds were characterized for morphology and mechanical properties and for the capability to support in vitro adhesion and proliferation of dermal fibroblasts in order to assess the system’s general biocompatibility. Adhesion and proliferation of endothelial cells and cardiac cells (cardiomyocytes and cardiac fibroblasts from rat fetuses onto PL-loaded patches was evaluated. Patches presented good elasticity and high stiffness suitable for in vivo adaptation to heart contraction. CS improved adhesion and proliferation of dermal fibroblasts, as proof of their biocompatibility. Moreover, they enhanced the adhesion and proliferation of endothelial cells, a crucial mediator of cardiac repair. Cell adhesion and proliferation could be related to elastic properties, which could favor cell motility. The presence of platelet lysate and CS was crucial for the adhesion and proliferation of cardiac cells and, in particular, of cardiomyocytes: G/CS scaffold embedded with PL appeared to selectively promote proliferation in cardiomyocytes but not cardiac fibroblasts. In conclusion, G/CS scaffold seems to be a promising system to assist myocardial-repair processes in young patient, preserving cardiomyocyte viability and preventing cardiac fibroblast proliferation, likely reducing subsequent uncontrolled collagen deposition by fibroblasts following repair.

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

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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).

Toxoplasma gondii, source to sea: higher contribution of domestic felids to terrestrial parasite loading despite lower infection prevalence.

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Vanwormer, Elizabeth; Conrad, Patricia A; Miller, Melissa A; Melli, Ann C; Carpenter, Tim E; Mazet, Jonna A K

2013-09-01

Environmental transmission of Toxoplasma gondii, a global zoonotic parasite, adversely impacts human and animal health. Toxoplasma is a significant cause of mortality in threatened Southern sea otters, which serve as sentinels for disease threats to people and animals in coastal environments. As wild and domestic felids are the only recognized hosts capable of shedding Toxoplasma oocysts into the environment, otter infection suggests land-to-sea pathogen transmission. To assess relative contributions to terrestrial parasite loading, we evaluated infection and shedding among managed and unmanaged feral domestic cats, mountain lions, and bobcats in coastal California, USA. Infection prevalence differed among sympatric felids, with a significantly lower prevalence for managed feral cats (17%) than mountain lions, bobcats, or unmanaged feral cats subsisting on wild prey (73-81%). A geographic hotspot of infection in felids was identified near Monterey Bay, bordering a high-risk site for otter infection. Increased odds of oocyst shedding were detected in bobcats and unmanaged feral cats. Due to their large populations, pet and feral domestic cats likely contribute more oocysts to lands bordering the sea otter range than native wild felids. Continued coastal development may influence felid numbers and distribution, increase terrestrial pathogens in freshwater runoff, and alter disease dynamics at the human-animal-environment interface.

Experimental reinfection of BALB/c mice with different recombinant type I/III strains of Toxoplasma gondii: involvement of IFN-³ and IL-10

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Brandão,Geane Peroni; Melo,Maria Norma; Gazzinelli,Ricardo Tostes; Caetano,Braulia Costa; Ferreira,Adriana Melo; Silva,Letícia Azevedo; Vitor,Ricardo Wagner Almeida

2009-01-01

To assess reinfection of BALB/c mice with different Toxoplasma gondii strains, the animals were prime infected with the non-virulent D8 strain and challenged with virulent recombinant strains. Thirty days after challenge, brain cysts were obtained from surviving BALB/c mice and inoculated in Swiss mice to obtain tachyzoites for DNA extraction and PCR-RFLP analysis to distinguish the different T. gondii strains present in possible co-infections. Anti-Toxoplasma immune responses were evaluated ...

Macrophages facilitate the excystation and differentiation of Toxoplasma gondii sporozoites into tachyzoites following oocyst internalization

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Toxoplasma gondii is a common parasite of humans and domestic animals, which is transmitted via oocysts in cat faeces or tissue cysts in contaminated meat. The oocyst and sporocyst walls are multilayered polymeric structures that protect the infective sporozoites from deleterious physical and chemic...

A more sensitive, efficient and ISO 17025 validated Magnetic Capture real time PCR method for the detection of archetypal Toxoplasma gondii strains in meat.

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Gisbert Algaba, Ignacio; Geerts, Manon; Jennes, Malgorzata; Coucke, Wim; Opsteegh, Marieke; Cox, Eric; Dorny, Pierre; Dierick, Katelijne; De Craeye, Stéphane

2017-11-01

Toxoplasma gondii is a globally prevalent, zoonotic parasite of major importance to public health. Various indirect and direct methods can be used for the diagnosis of toxoplasmosis. Whereas serological tests are useful to prove contact with the parasite has occurred, the actual presence of the parasite in the tissues of a seropositive animal is not demonstrated. For this, a bioassay is still the reference method. As an alternative, various PCR methods have been developed, but due to the limited amount of sample that can be tested, combined with a low tissue cyst density, those have proved to be insufficiently sensitive. A major improvement of the sensitivity was achieved with magnetic capture-based DNA extraction. By combining the hybridization of specific, biotinylated probes with the capture of those probes with streptavidin-coated paramagnetic beads, T. gondii DNA can selectively be "fished out" from a large volume of meat lysate. Still, several studies showed an insufficient sensitivity compared with the mouse bioassay. Here we present a method that is more sensitive (99% limit of detection: 65.4 tachyzoites per 100g of meat), economical and reliable (ISO 17025 validated) by adding a non-competitive PCR inhibition control (co-capture of cellular r18S) and making the release of the target DNA from the streptavidin-coated paramagnetic beads UV-dependent. The presented results demonstrate the potential of the modified Magnetic Capture real time PCR as a full alternative to the mouse bioassay for the screening of various types of tissues and meat, with the additional advantage of being quantitative. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

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

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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

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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 ...

Toxoplasma gondii infection in Kyrgyzstan: seroprevalence, risk factor analysis, and estimate of congenital and AIDS-related toxoplasmosis.

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Gulnara Minbaeva

Full Text Available BACKGROUND: HIV-prevalence, as well as incidence of zoonotic parasitic diseases like cystic echinococcosis, has increased in the Kyrgyz Republic due to fundamental socio-economic changes after the breakdown of the Soviet Union. The possible impact on morbidity and mortality caused by Toxoplasma gondii infection in congenital toxoplasmosis or as an opportunistic infection in the emerging AIDS pandemic has not been reported from Kyrgyzstan. METHODOLOGY/PRINCIPAL FINDINGS: We screened 1,061 rural and 899 urban people to determine the seroprevalence of T. gondii infection in 2 representative but epidemiologically distinct populations in Kyrgyzstan. The rural population was from a typical agricultural district where sheep husbandry is a major occupation. The urban population was selected in collaboration with several diagnostic laboratories in Bishkek, the largest city in Kyrgyzstan. We designed a questionnaire that was used on all rural subjects so a risk-factor analysis could be undertaken. The samples from the urban population were anonymous and only data with regard to age and gender was available. Estimates of putative cases of congenital and AIDS-related toxoplasmosis in the whole country were made from the results of the serology. Specific antibodies (IgG against Triton X-100 extracted antigens of T. gondii tachyzoites from in vitro cultures were determined by ELISA. Overall seroprevalence of infection with T. gondii in people living in rural vs. urban areas was 6.2% (95%CI: 4.8-7.8 (adjusted seroprevalence based on census figures 5.1%, 95% CI 3.9-6.5, and 19.0% (95%CI: 16.5-21.7 (adjusted 16.4%, 95% CI 14.1-19.3, respectively, without significant gender-specific differences. The seroprevalence increased with age. Independently low social status increased the risk of Toxoplasma seropositivity while increasing numbers of sheep owned decreased the risk of seropositivity. Water supply, consumption of unpasteurized milk products or undercooked

Detection of toxoplasma-specific immunoglobulin G in human sera: performance comparison of in house Dot-ELISA with ECLIA and ELISA.

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Teimouri, Aref; Modarressi, Mohammad Hossein; Shojaee, Saeedeh; Mohebali, Mehdi; Zouei, Nima; Rezaian, Mostafa; Keshavarz, Hossein

2018-05-08

In the current study, performance of electrochemiluminescence immunoassay (ECLIA) in detection of anti-toxoplasma IgG in human sera was compared with that of enzyme-linked immunosorbent assay (ELISA). Furthermore, performance of an in house Dot-ELISA in detection of anti-toxoplasma IgG was compared with that of ECLIA and ELISA. In total, 219 human sera were tested to detect anti-toxoplasma IgG using Dynex DS2® and Roche Cobas® e411 Automated Analyzers. Discordant results rechecked using immunofluorescence assay (IFA). Then, sera were used in an in house Dot-ELISA to assess toxoplasma-specific IgG. Of the 219 samples, two samples were found undetermined using ECLIA but reactive using ELISA. Using IFA, the two sera were reported unreactive. Furthermore, two samples were found reactive using ECLIA and unreactive using ELISA. These samples were reported reactive using IFA. The overall agreement for the two former methods was 98% (rZ0.98.1; P house Dot-ELISA included sensitivity of 79.5, specificity of 78.2, and accuracy of 78.9%, compared to ECLIA and ELISA. Positive and negative predictive values included 82.9 and 74.2%, respectively. A 100% sensitivity was found in in house Dot-ELISA for highly reactive sera in ECLIA and ELISA. ECLIA is appropriate for the first-line serological screening tests and can replace ELISA due to high speed, sensitivity, and specificity, particularly in large laboratories. Dot-ELISA is a rapid, sensitive, specific, cost-effective, user-friendly, and field-portable technique and hence can be used for screening toxoplasmosis, especially in rural fields or less equipped laboratories.

Seroprevalence and risk factors for toxoplasma infection among pregnant women in Aydin province, Turkey

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Turkmen Munevver

2005-06-01

Full Text Available Abstract Background The aims of the present study were to determine the prevalence of toxoplasmosis in pregnant women at first trimester of their pregnancy and to follow up the seroconversion for next two trimesters, and to identify the risk factors and possible contamination routes in Aydin province, Turkey. Method The sample size was calculated as 423 on a prevalence of 50%, d=0.05 at a confidence level of 95% with 10% addition. It was a cross-sectional study with multistage sampling. After a questionnaire applied to the pregnant women, anti-Toxoplasma IgG antibodies were studied with ELISA and IFA, values in conflict with DA test, where IgM antibodies were studied with ELISA and for borderline or positive values of IgM avidity test was used. Results The mean age of 389 (92.9% of pregnant women in the study was 24.28+/-4.56 years, the seroprevalence of anti-Toxoplasma IgG antibodies for toxoplasmosis was 30.1%. Seroprevalence was increased with age (p=0.001 and with drinking water consumption other than bottled water (p=0.042. No significant relations were observed between anti-Toxoplasma IgG antibodies and education level, being native or migrant, abortion history, consumption of meat, vegetable and milk/milk products, personal or kitchen hygiene habits, cat owning at home of the pregnant women. No IgM antibody was detected. Conclusion One of every three pregnant women in Aydin was at risk of toxoplasmosis at the first trimester of their pregnancy. Increased seroprevalance with age was a predictable result because of increasing time of exposure. Increased seroprevalence with consumption of municipal and uncontrolled water (well/spring water supplies was similar with latest epidemiological findings.

Advantages of bioconjugated silica-coated nanoparticles as an innovative diagnosis for human toxoplasmosis.

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Aly, Ibrahim; Taher, Eman E; El Nain, Gehan; El Sayed, Hoda; Mohammed, Faten A; Hamad, Rabab S; Bayoumy, Elsayed M

2018-01-01

Nanotechnology is a promising arena for generating new applications in Medicine. To successfully functionalised nanoparticles for a given biomedical application, a wide range of chemical, physical and biological factors have to be taken into account. Silica-coated nanoparticles, (SiO2NP) exhibit substantial diagnostic activity owing to their large surface to volume ratios and crystallographic surface structure. This work aimed to evaluate the advantage of bioconjugation of SiO2NP with PAb against Toxoplasma lyzate antigen (TLA) as an innovative diagnostic method for human toxoplasmosis. This cross-sectional study included 120 individuals, divided into Group I: 70 patients suspected for Toxoplasma gondii based on the presence of clinical manifestation. Group II: 30 patients harboring other parasites than T. gondii Group III: 20 apparently healthy individuals free from toxoplasmosis and other parasitic infections served as negative control. Detection of circulating Toxoplasma antigen was performed by Sandwich ELISA and Nano-sandwich ELISA on sera and pooled urine of human samples. Using Sandwich ELISA, 10 out of 70 suspected Toxoplasma-infected human serum samples showed false negative and 8 out of 30 of other parasites groups were false positive giving 85.7% sensitivity and 84.0% specificity, while the sensitivity and specificity were 78.6% and 70% respectively in urine samples. Using Nano-Sandwich ELISA, 7 out of 70 suspected Toxoplasma-infected human samples showed false negative results and the sensitivity of the assay was 90.0%, while 4 out of 30 of other parasites groups were false positive giving 92.0% specificity, while the sensitivity and specificity were 82.6% and 80% respectively in urine samples. In conclusion, our data demonstrated that loading SiO2 nanoparticles with pAb increased the sensitivity and specificity of Nano-sandwich ELISA for detection of T.gondii antigens in serum and urine samples, thus active (early) and light infections could be easily

Detection of endotoxins in radiopharmaceutical preparations. II. Comparison of the sensitivity of methods using the rabbit and the Limulus amoebocyte lysate for the detection of endotoxins

Energy Technology Data Exchange (ETDEWEB)

Bruneau, J; Cohen, Y; Merlin, L; Peysson, S

1986-01-01

The rise of the rabbit internal temperature after i.v. injection of an endotoxin solution is proportional to concentration. Gelation of Limulus amoebocyte, when in presence of an endotoxin solution, is also related to concentration. We compared the sensitivity of these two methods. With our experimental procedure, the rabbit is sensitive to a 0.40 ng/mL solution and the Limulus amoebocyte lysate to a 0.14 ng/mL solution. The rabbit sensitivity increase is related to the per kilogramme injected volume, whereas sensitivity is not related to the volume to check in the case of the lysate.

Prevalence of antibodies to Leishmania infantum and Toxoplasma gondii in horses from the north of Portugal

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Background Leishmania infantum and Toxoplasma gondii are protozoa with zoonotic and economic importance. Prevalences of antibodies to these agents were assessed in 173 horses from the north of Portugal. Findings Antibodies to L. infantum were detected by the direct agglutination test (DAT); seven (...

Characterization of Toxoplasma gondii-specific T cells recovered from vitreous fluid of patients with ocular toxoplasmosis

NARCIS (Netherlands)

Feron, E. J.; Klaren, V. N.; Wierenga, E. A.; Verjans, G. M.; Kijlstra, A.

2001-01-01

The mechanisms involved in reactivations of latent ocular Toxoplasma gondii (Tg) infections in immunocompetent patients are poorly understood. In view of the possible role of T cells in the immunopathogenesis of the disease, ocular infiltrating T cells obtained from patients with recurrent ocular

Behavioural and biochemical profiles in rats infected with Toxoplasma gondii or lipopolysaccharide: animal models of schizophrenia

Czech Academy of Sciences Publication Activity Database

Tejkalová, H.; Kodym, P.; Kačer, P.; Klaschka, Jan; Horáček, J.

2013-01-01

Roč. 24, e-Suppl. 1 (2013), e22 ISSN 0955-8810. [Biennal meeting of the EBPS /15./. 06.09.2013-09.09.2013, La Rochelle] Institutional support: RVO:67985807 Keywords : animal models * schizophrenia * behaviour * LPS * Toxoplasma gondii Subject RIV: FH - Neurology

PREVALENCE OF ANTIBODIES AGAINST TOXOPLASMA GONDII IN POLAR BEARS (URSUS MARITIMUS) FROM SVALBARD AND EAST GREENLAND

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Serum samples from 419 polar bears (Ursus maritimus) from Svalbard and the Barents Sea (collected 1990 - 2000) and 108 polar bears from East Greenland (collected 1999 - 2004) were assayed for antibodies against Toxoplasma gondii using the modified agglutination test (MAT). Antibody prevalences were ...

Seroprevalence of Toxoplasma gondii in free-living Amazon river dolphins (Inia geoffrensis) from central Amazon, Brazil

Science.gov (United States)

Toxoplasma gondii is an important pathogen in aquatic mammals and its presence in these animals may indicate water contamination of aquatic environment by oocysts. Serum samples from 95 dolphins from free-living Amazon River dolphins (Inia geoffrensis) from Sustainable Development Reserve Mamirauá (...

Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

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Hasanzadeh, Leila; Ghaznavi-Rad, Ehsanollah; Soufian, Safieh; Farjadi, Vahideh; Abtahi, Hamid

2013-01-01

Objective(s) : Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA) is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity. Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3) pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis . PMID:23997913

Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

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Leila Hasanzadeh

2013-07-01

Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

Infecção per os de gatos com formas vegetativas de Toxoplasma gondii Nicolle & Manceaux, 1909 sem produção de oocistos Oral infections of domestic cats with vegetative forms of Toxoplasma gondii Nicolle & Manceaux, 1909 without oocyst production

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Felippe Nery-Guimarães

1973-01-01

Full Text Available Quatro grupos de 6 gatos (24 gatos recém-nascidos e desmamados receberam "per os", respectivamente, suspensões de toxoplasmas de camundongos com 3-4 dias de infecção, de 4 amostras de T. gondii. Cada grupo teve um gato testemunha. Nenhum dos gatos de experiência eliminou oocistos atribuíveis a T. gondii, em períodos de observação de 6 a 20 dias; e suas fezes, conservadas 2-4 dais em bicromato de potássio a 2,5% e ministradas "per os" a camundongos, não induziram toxoplasmose nesses roedores. Com exceção dos que eram portadores de Isospora, os gatos não mostraram formas evolutivas de coccídios no epitélio intestinal. Em todos os grupos a infecção toxoplásmica foi comprovada pela positividade da reação de Sabin & Feldman (1:16 a 1:1024; e pelo isolamento de toxoplasmas pela inoculação de triturados dos seus principais órgãos em camundongos indicadores. De um modo geral, os gatos mais crescidos não mostraram sinais de doença, porém os outros, e principalmente os recém-nascidos adoeceram e vários morreram de toxoplasmose sistêmica: esplenite, hepatite, enterite, penumonia e, mais raramente, miocardite e encefalite. Os toxoplasmas foram encontrados em todos esses órgãos e, tamém, nos rins e supra-renais.Vegetative forms of 4 strains of Toxoplasma from peritoneal fluid of mice with 3-4 days of acute infection were orally administered to 4 groups of 6 newborn and wealing kittens respectivelly. Each group had a control kitten. All kittens were observed for eriods of 6-20 days ans never passed in their faeces oocysts attributabel to T. gondii. On the other hand, their faces after 2-4 days in potassium dichromate at 2.5% inoculated orally in mice didn't produce Toxoplasma infection in these animals; and with exception of the cats that have had spontaneous isosporosis (I. felis and/or I. rivolta we didn´t see evolutive forms of Coccidia in the intestinal wall of the cats. In all cat groups the toxoplasmic infection was

Comparative Analysis of Click Chemistry Mediated Activity-Based Protein Profiling in Cell Lysates

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Yinliang Yang

2013-10-01

Full Text Available Activity-based protein profiling uses chemical probes that covalently attach to active enzyme targets. Probes with conventional tags have disadvantages, such as limited cell permeability or steric hindrance around the reactive group. A tandem labeling strategy with click chemistry is now widely used to study enzyme targets in situ and in vivo. Herein, the probes are reacted in live cells, whereas the ensuing detection by click chemistry takes place in cell lysates. We here make a comparison of the efficiency of the activity-based tandem labeling strategy by using Cu(I-catalyzed and strain-promoted click chemistry, different ligands and different lysis conditions.

Toxoplasma gondii and Epilepsy.

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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.

The Effect of Toxoplasma gondii on Animal Behavior: Playing Cat and Mouse

OpenAIRE

Webster, Joanne P.

2007-01-01

A convincing body of evidence now exists to indicate that the ubiquitous protozoan Toxoplasma gondii can cause permanent behavioral changes in its host, even as a consequence of adult-acquired latent infection. Such behavioral alterations appear to be the product of strong selective pressures for the parasite to enhance transmission from its intermediate host reservoir, primarily rodent, to its feline definitive host, wherein sexual reproduction can occur and the life cycle completed. This ar...

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

Isolation of viable Toxoplasma gondii, molecular characterization, and seroprevalence in elk (Cervus canadensis) in Pennsylvania, USA

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Toxoplasmosis is a worldwide zoonosis. The ingestion of uncooked/undercooked meat and consumption of water contaminated with Toxoplasma gondii oocysts excreted by felids are the main modes of transmission of this parasite. Thousands of wild cervids are hunted or killed in traffic accidents yearly bu...

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

NARCIS (Netherlands)

Cornelissen, J.B.W.J.; Giessen, van der J.W.B.; Takumi, K.; Teunis, P.F.M.; Wisselink, H.J.

2014-01-01

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.

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

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

Prevalence of antibodies to Leishmania infantum and Toxoplasma gondii in horses from the north of Portugal

NARCIS (Netherlands)

Lopes, Ana Patrícia; Sousa, Susana; Dubey, Jp; Ribeiro, Ana J.; Silvestre, Ricardo; Cotovio, Mário; Schallig, Henk Dfh; Cardoso, Luís; Cordeiro-da-Silva, Anabela

2013-01-01

Leishmania infantum and Toxoplasma gondii are protozoa with zoonotic and economic importance. Prevalences of antibodies to these agents were assessed in 173 horses from the north of Portugal. Antibodies to L. infantum were detected by the direct agglutination test (DAT); seven (4.0%) horses were

Tailor-made purified human platelet lysate concentrated in neurotrophins for treatment of Parkinson's disease.

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Chou, Ming-Li; Wu, Joe-Wei; Gouel, Flore; Jonneaux, Aurélie; Timmerman, Kelly; Renn, Ting-Yi; Laloux, Charlotte; Chang, Hung-Ming; Lin, Liang-Tzung; Devedjian, Jean-Christophe; Devos, David; Burnouf, Thierry

2017-10-01

Human platelet lysates (PLs), which contain multiple neurotrophins, have been proposed for treating neurodegenerative disorders, including Parkinson's disease (PD). However, current PLs suspended in plasma have high protein content and contain fibrinogen/fibrin and, following activation, also proteolytic and thrombogenic enzymes. Upon brain administration, such PLs may saturate the cerebrospinal fluid and exert neurotoxicity. We assessed whether purified PLs, concentrated in neurotrophins, protected dopaminergic neurons in PD models. Platelet concentrates were collected by apheresis and centrifuged to eliminate plasma and recover the platelets. Platelets were lysed by freeze-thaw cycles, and the 10-fold concentrated platelet pellet lysates (PPLs) were heat-treated (at 56 °C for 30 min). The heat-treated PPLs were low in total proteins, depleted in both plasma and platelet fibrinogen, and devoid of thrombogenic and proteolytic activities. They exerted very high neuroprotective activity when non-oncogenic, Lund human mesencephalic (LUHMES) cells that had differentiated into dopaminergic neurons were exposed to the MPP + neurotoxin. Heat treatment improved the neuroprotection and inactivated the neurotoxic blood-borne hepatitis C virus. PPL did not induce inflammation in BV2 microglial cells and inhibited COX-2 expression upon lipopolysaccharide exposure. Intranasal administration in mice revealed (a) diffusion of neurotrophins in the striatum and cortex, and (b) MPTP intoxication neuroprotection in the substantia nigra and striatum and the absence of neuroinflammation. These dedicated heat-treated PPLs can be a safe and valuable candidate for a therapeutic strategy for PD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Qualitative assessment for Toxoplasma gondii exposure risk associated with consumption of meat products in the United States

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Toxoplasma gondii is a global protozoan parasite capable of infecting most warm-blooded animals. Although healthy adult humans generally have no symptoms after postnatally-acquired infection, severe illness does occur in immunocompromised individuals. Epidemiological studies have demonstrated that c...

The effects of platelet lysate on maturation, fertilization and embryo development of NMRI mouse oocytes at germinal vesicle stage.

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Pazoki, Hassan; Eimani, Hussein; Farokhi, Farah; Shahverdi, Abdol-Hossein; Tahaei, Leila Sadat

2016-04-01

Improving in vitro maturation could increase the rate of pregnancy from oocytes matured in vitro. Consequently, patients will be prevented from using gonadotropin with its related side effects. In this study, the maturation medium was enriched by platelet lysate (PL), then maturation and subsequent developments were monitored. Oocytes at germinal vesicle stage with cumulus cells (cumulus-oocyte complex) and without cumulus cells (denuded oocytes) were obtained from mature female mice. The maturation medium was enriched by 5 and 10 % PL and 5 % PL + 5 % fetal bovine serum (FBS) as experimental groups; the control groups' media consisted of 5 and 10 % FBS. After 18 h, the matured oocytes were collected and, after fertilization, subsequent development was monitored. The rates of maturation, fertilization and 2-cell embryo development for the denuded oocyte groups in experimental media 5 % PL and 5 % PL + 5 % FBS were significantly higher than those of the control groups ( P platelet lysate could improve the maturation rate in the absence of granulosa cells compared to media with FBS. This extract also had positive effects on fertilization and embryo development.

Rapid and simple purification of elastin-like polypeptides directly from whole cells and cell lysates by organic solvent extraction.

Science.gov (United States)

VerHeul, Ross; Sweet, Craig; Thompson, David H

2018-03-26

Elastin-like polypeptides (ELP) are a well-known class of proteins that are being increasingly utilized in a variety of biomedical applications, due to their beneficial physicochemical properties. A unifying feature of ELP is their demonstration of a sequence tunable inverse transition temperature (Tt) that enables purification using a simple, straightforward process called inverse transition cycling (ITC). Despite the utility of ITC, the process is inherently limited to ELP with an experimentally accessible Tt. Since the underlying basis for the ELP Tt is related to its high overall hydrophobicity, we anticipated that ELP would be excellent candidates for purification by organic extraction. We report the first method for rapidly purifying ELP directly from whole E. coli cells or clarified lysates using pure organic solvents and solvent mixtures, followed by aqueous back extraction. Our results show that small ELP and a large ELP-fusion protein can be isolated in high yield from whole cells or cell lysates with greater than 95% purity in less than 30 min and with very low levels of LPS and DNA contamination.

Molecular Detection of Toxoplasma gondii Oocytes in the Soil from the Public Parks of the Arak City, Iran

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Hadis Solymane

2014-02-01

Conclusion: This study showed soils of public parks in the Arak city were contaminated to oocyst of Toxoplasma. Also molecular method for the detection of parasites in the soil was more suitable than staining method.

Patogenicidade e virulência de Toxoplasma gondii isolado de suínos de criação artesanal no sul do Brasil

OpenAIRE

Oliveira,Plínio Aguiar de; Oliveira,Fernando Caetano de; Faria,Laura Maria Jorge de; Cademartori,Beatris Gonzalez; Marcolongo-Pereira,Clairton; Coelho,Ana Carolina Barreto; Pappen,Felipe Geraldo; Farias,Nara Amélia

2014-01-01

Estudos com Toxoplasma gondii em suínos são relevantes porque seus produtos e subprodutos fazem parte da cadeia alimentar do ser humano. As principais vias de transmissão deste agente são o carnivorismo, fecal-oral e congênita. Seis isolados de Toxoplasma gondii de suínos de criação artesanal foram avaliados quanto à patogenicidade e virulência em camundongos suíços albinos. A suspensão de taquizoítos utilizada nos testes foi obtida através da punção ou lavagem da cavidade peritoneal de camun...

Detecção de anticorpos para Toxoplasma gondii em soro de suínos criados e abatidos em frigoríficos da região da grande Porto Alegre-RS, Brasil Detection of antibodies against Toxoplasma gondii in sera from swine bred and slaughtered in the great Porto Alegre-RS abbattoirs, Brazil

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Cristina Germani Fialho

2003-10-01

Full Text Available No presente trabalho, objetivou-se contribuir com dados sobre a freqüência de sororeagentes para Toxoplasma gondii em suínos criados e abatidos na Região da Grande Porto Alegre e fornecer subsídios sobre a importância da transmissão deste protozoário, por suínos. Foram coletadas amostras de 240 suínos em frigoríficos da região. A freqüência de anticorpos anti- Toxoplasma gondii, determinada através da técnica de hemaglutinação indireta, foi de 20 % de soros iguais ou superiores a diluição 1:64. Na técnica de imunofluorescência indireta, foram encontrados 33,75% de soro com diluição iguais a 1:16 ou superiores.This report objectived to contribuite with data about the antibodies occurence of Toxoplasma gondii in swine bred and slaughtered in the area of Great Porto Alegre- RS, Brazil. The data should supply with subsidies on the importance of this protozoan transmission through swines. Samples were taken from 240 swines at slaughterhouses in that region. The frequency of anti-Toxoplasma gondii antibodies, determinanet through the indirect hemagglutination technic was of 20% of serum equal or superior to 1:64 dilution. In the indirect immunofluorescence technic was found 33.75% in serum with a diluition equal to 1:16 or superior.

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...

Purification of Proteins From Cell-Culture Medium or Cell-Lysate by High-Speed Counter-Current Chromatography Using Cross-Axis Coil Planet Centrifuge

Science.gov (United States)

Shibusawa, Yoichi; Ito, Yoichiro

2014-01-01

This review describes protein purifications from cell culture medium or cell-lysate by high speed counter-current chromatography using the cross-axis coil planet centrifuge. Purifications were performed using aqueous two phase systems composed of polyethylene glycols and dextrans. PMID:25360182

The SnSAG merozoite surface antigens of Sarcocystis neurona are expressed differentially during the bradyzoite and sporozoite life cycle stages.

Science.gov (United States)

Gautam, A; Dubey, J P; Saville, W J; Howe, D K

2011-12-29

Sarcocystis neurona is a two-host coccidian parasite whose complex life cycle progresses through multiple developmental stages differing at morphological and molecular levels. The S. neurona merozoite surface is covered by multiple, related glycosylphosphatidylinositol-linked proteins, which are orthologous to the surface antigen (SAG)/SAG1-related sequence (SRS) gene family of Toxoplasma gondii. Expression of the SAG/SRS proteins in T. gondii and another related parasite Neospora caninum is life-cycle stage specific and seems necessary for parasite transmission and persistence of infection. In the present study, the expression of S. neurona merozoite surface antigens (SnSAGs) was evaluated in the sporozoite and bradyzoite stages. Western blot analysis was used to compare SnSAG expression in merozoites versus sporozoites, while immunocytochemistry was performed to examine expression of the SnSAGs in merozoites versus bradyzoites. These analyses revealed that SnSAG2, SnSAG3 and SnSAG4 are expressed in sporozoites, while SnSAG5 was appeared to be downregulated in this life cycle stage. In S. neurona bradyzoites, it was found that SnSAG2, SnSAG3, SnSAG4 and SnSAG5 were either absent or expression was greatly reduced. As shown for T. gondii, stage-specific expression of the SnSAGs may be important for the parasite to progress through its developmental stages and complete its life cycle successfully. Thus, it is possible that the SAG switching mechanism by these parasites could be exploited as a point of intervention. As well, the alterations in surface antigen expression during different life cycle stages may need to be considered when designing prospective approaches for protective vaccination. Copyright © 2011 Elsevier B.V. All rights reserved.

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...

Seropositive pigs to Toxoplasma gondii (Apicomplexa: Toxoplasmatinae sent to slaughter and destined for human consumption

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Wanderley M. de Almeida

2015-12-01

Full Text Available ABSTRACT. de Almdeida W., Miranda Z.B., Flausino W., Coelho C.D., Fonseca A.B.M. & Lopes C.W.G. [Seropositive pigs to Toxoplasma gondii (Apicomplexa: Toxoplasmatinae sent to slaughter and destined for human consumption.] Suínos sororreagentes a Toxoplasma gondii (Apicomplexa: Toxoplasmatinae enviados para abate e destinados ao consumo humano. Revista Brasileira de Medicina Veterinária, 37(4:397-400, 2015. Curso de Pós-Graduação em Medicina Veterinária - Higiene Veterinária e Processamento Tecnológico de Produtos de Origem Animal, Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brasil Filho, 64, Vital Brazil, Niterói, RJ 24230-340, Brasil. E-mail: wanderleyma@yahoo.com.br This study aimed to determine the frequency of pigs seropositive to Toxoplasma gondii by indirect immunofluorescence assay with cutoff 1:16. Of blood samples collected at slaughter, 250 of them were from animals raised in the State of Minas Gerais; while 181 were from the State of Rio de Janeiro with a total of 431 examined samples. Of these, 19/250 (4.41% of MG and 39/181 (9.04% of RJ, determining a total of 13.45% seropositive animals. Regardless of slaughter be under the control of the inspection service, the precedence of the animals was highly significant (p = 0.0001 in the number of seropositive animals. Although the percentage of seropositive animals to T. gondii from both regions studied in this work, and from the point of view of a public health problem, pork and its frescal type products may continue to be considered as a source of infection of this coccidia for humans, if they are consumed as raw or undercooked.

Characterization of IgG monoclonal antibody targeted to both tissue cyst and sporocyst walls of Toxoplasma gondii

Science.gov (United States)

Toxoplasma gondii infects approximately one third of the human population and animals habiting terrestrial and aquatic environments. Its environmentally resistant oocysts are excreted by felids, and the stage encysted in tissues (tissue cysts), are important in the horizontal transmission of T. gon...

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...

Occurrence of Toxoplasma gondii antibodies in birds from the Atlantic Forest, state of São Paulo, Brazil

Science.gov (United States)

Avians are considered important intermediate hosts for Toxoplasma gondii because they serve as source of infection for Felidae, which shed environmentally resistant oocysts after ingesting infected tissues. Little is known of the epidemiology of toxoplasmosis in wild birds. In the present study, ant...

Seroprevalence of Toxoplasma gondii in American Black Bears ( Ursus americanus ) of the Central Appalachians, USA.

Science.gov (United States)

Cox, John J; Murphy, Sean M; Augustine, Ben C; Guthrie, Joseph M; Hast, John T; Maehr, Sutton C; McDermott, Joseph

2017-07-01

We assessed Toxoplasma gondii seroprevalence in 53 free-ranging American black bears ( Ursus americanus ) in the Central Appalachian Mountains, US. Seroprevalence was 62% with no difference between males and females or between juvenile and adult bears. Wildlife agencies should consider warnings in hunter education programs to reduce the chances for human infection from this source.

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...

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 ...

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

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Isabel Correa

2018-03-01

Full Text Available Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1 specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells.

Science.gov (United States)

Correa, Isabel; Ilieva, Kristina M; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F; Tutt, Andrew N J; Nestle, Frank O; Karagiannis, Panagiotis; Lacy, Katie E; Karagiannis, Sophia N

2018-01-01

Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

Science.gov (United States)

Correa, Isabel; Ilieva, Kristina M.; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F.; Tutt, Andrew N. J.; Nestle, Frank O.; Karagiannis, Panagiotis; Lacy, Katie E.; Karagiannis, Sophia N.

2018-01-01

Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires. PMID:29628923

Comparative study on the antioxidant and anti-Toxoplasma activities of vanillin and its resorcinarene derivative.

Science.gov (United States)

Oliveira, Claudio B S; Meurer, Ywlliane S R; Oliveira, Marianne G; Medeiros, Wendy M T Q; Silva, Francisco O N; Brito, Ana C F; Pontes, Daniel de L; Andrade-Neto, Valter F

2014-05-07

A resorcinarene derivative of vanillin, resvan, was synthesized and characterized by spectroscopic techniques. We measured the cytotoxicity (in vivo and in vitro), antioxidant and anti-Toxoplasma activities of vanillin and the resorcinarene compound. Here we show that vanillin has a dose-dependent behavior with IC50 of 645 µg/mL through an in vitro cytotoxicity assay. However, we could not observe any cytotoxic response at higher concentrations of resvan (IC50 > 2,000 µg/mL). The in vivo acute toxicity assays of vanillin and resvan exhibited a significant safety margin indicated by a lack of systemic and behavioral toxicity up to 300 mg/kg during the first 30 min, 24 h or 14 days after administration. The obtained derivative showed greater antioxidative activity (84.9%) when comparing to vanillin (19.4%) at 1,000 μg/mL. In addition, vanillin presents anti-Toxoplasma activity, while resvan does not show that feature. Our findings suggest that this particular derivative has an efficient antioxidant activity and a negligible cytotoxic effect, making it a potential target for further biological investigations.

A simple and economic slide micro-immunoenzymatic (Micro-SIA test for epidemiological studies of toxoplasmosis

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Mara Rosenzvit

1994-03-01

Full Text Available A slide micro-immunoenzymatic assay (micro-SIA to detectantibodies to non-particulate Toxoplasma gondii antigens is described. This assay allows the diagnosis of toxoplasmosis infection in about 1 hr. Twenty-four determinations can be performed per slide. Five hundred ng of antigen and 5 or 10 µl drop of each reactive are necessary per well. The clear contrast of colours obtained for negative and positive sera after the test is finished, allows direct discrimination of the results. However, it is possible to quantify the results of the reaction using a minireader. Sera dilution cutoff value, determined as themost frequent titre for the general population, is 1:100. The toxoplasma micro-SIA correlates well with indirect immunofluorescence (IIF, its sensitivity is atleast three times as much as IIF. The test has an intra and inter assay variation coefficient of 5.46 per cent and of 6.24 per cent respectively. Sera obtained at random from argentinian people were analyzed and a 56 per cent of infection was found. The main features of the Toxoplasma micro-SIA are its simplicity, sensitivity, reproducibility, and the virtual absence of background making it very suitable for screening tests.

The Crystal Structure of Toxoplasma gondii Pyruvate Kinase 1

Energy Technology Data Exchange (ETDEWEB)

Bakszt, R.; Wernimont, A; Allali-Hassani, A; Mok, M; Hills, T; Hui, R; Pizarro, J

2010-01-01

Pyruvate kinase (PK), which catalyzes the final step in glycolysis converting phosphoenolpyruvate to pyruvate, is a central metabolic regulator in most organisms. Consequently PK represents an attractive therapeutic target in cancer and human pathogens, like Apicomplexans. The phylum Aplicomplexa, a group of exclusively parasitic organisms, includes the genera Plasmodium, Cryptosporidium and Toxoplasma, the etiological agents of malaria, cryptosporidiosis and toxoplasmosis respectively. Toxoplasma gondii infection causes a mild illness and is a very common infection affecting nearly one third of the world's population. We have determined the crystal structure of the PK1 enzyme from T. gondii, with the B domain in the open and closed conformations. We have also characterized its enzymatic activity and confirmed glucose-6-phosphate as its allosteric activator. This is the first description of a PK enzyme in a closed inactive conformation without any bound substrate. Comparison of the two tetrameric TgPK1 structures indicates a reorientation of the monomers with a concomitant change in the buried surface among adjacent monomers. The change in the buried surface was associated with significant B domain movements in one of the interacting monomers. We hypothesize that a loop in the interface between the A and B domains plays an important role linking the position of the B domain to the buried surface among monomers through two {alpha}-helices. The proposed model links the catalytic cycle of the enzyme with its domain movements and highlights the contribution of the interface between adjacent subunits. In addition, an unusual ordered conformation was observed in one of the allosteric binding domains and it is related to a specific apicomplexan insertion. The sequence and structural particularity would explain the atypical activation by a mono-phosphorylated sugar. The sum of peculiarities raises this enzyme as an emerging target for drug discovery.

The crystal structure of Toxoplasma gondii pyruvate kinase 1.

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Rebecca Bakszt

2010-09-01

Full Text Available Pyruvate kinase (PK, which catalyzes the final step in glycolysis converting phosphoenolpyruvate to pyruvate, is a central metabolic regulator in most organisms. Consequently PK represents an attractive therapeutic target in cancer and human pathogens, like Apicomplexans. The phylum Aplicomplexa, a group of exclusively parasitic organisms, includes the genera Plasmodium, Cryptosporidium and Toxoplasma, the etiological agents of malaria, cryptosporidiosis and toxoplasmosis respectively. Toxoplasma gondii infection causes a mild illness and is a very common infection affecting nearly one third of the world's population.We have determined the crystal structure of the PK1 enzyme from T. gondii, with the B domain in the open and closed conformations. We have also characterized its enzymatic activity and confirmed glucose-6-phosphate as its allosteric activator. This is the first description of a PK enzyme in a closed inactive conformation without any bound substrate. Comparison of the two tetrameric TgPK1 structures indicates a reorientation of the monomers with a concomitant change in the buried surface among adjacent monomers. The change in the buried surface was associated with significant B domain movements in one of the interacting monomers.We hypothesize that a loop in the interface between the A and B domains plays an important role linking the position of the B domain to the buried surface among monomers through two α-helices. The proposed model links the catalytic cycle of the enzyme with its domain movements and highlights the contribution of the interface between adjacent subunits. In addition, an unusual ordered conformation was observed in one of the allosteric binding domains and it is related to a specific apicomplexan insertion. The sequence and structural particularity would explain the atypical activation by a mono-phosphorylated sugar. The sum of peculiarities raises this enzyme as an emerging target for drug discovery.

The crystal structure of Toxoplasma gondii pyruvate kinase 1.

Science.gov (United States)

Bakszt, Rebecca; Wernimont, Amy; Allali-Hassani, Abdellah; Mok, Man Wai; Hills, Tanya; Hui, Raymond; Pizarro, Juan C

2010-09-14

Pyruvate kinase (PK), which catalyzes the final step in glycolysis converting phosphoenolpyruvate to pyruvate, is a central metabolic regulator in most organisms. Consequently PK represents an attractive therapeutic target in cancer and human pathogens, like Apicomplexans. The phylum Aplicomplexa, a group of exclusively parasitic organisms, includes the genera Plasmodium, Cryptosporidium and Toxoplasma, the etiological agents of malaria, cryptosporidiosis and toxoplasmosis respectively. Toxoplasma gondii infection causes a mild illness and is a very common infection affecting nearly one third of the world's population. We have determined the crystal structure of the PK1 enzyme from T. gondii, with the B domain in the open and closed conformations. We have also characterized its enzymatic activity and confirmed glucose-6-phosphate as its allosteric activator. This is the first description of a PK enzyme in a closed inactive conformation without any bound substrate. Comparison of the two tetrameric TgPK1 structures indicates a reorientation of the monomers with a concomitant change in the buried surface among adjacent monomers. The change in the buried surface was associated with significant B domain movements in one of the interacting monomers. We hypothesize that a loop in the interface between the A and B domains plays an important role linking the position of the B domain to the buried surface among monomers through two α-helices. The proposed model links the catalytic cycle of the enzyme with its domain movements and highlights the contribution of the interface between adjacent subunits. In addition, an unusual ordered conformation was observed in one of the allosteric binding domains and it is related to a specific apicomplexan insertion. The sequence and structural particularity would explain the atypical activation by a mono-phosphorylated sugar. The sum of peculiarities raises this enzyme as an emerging target for drug discovery.

Pesquisa de anticorpos anti Toxoplasma gondii em fluidos intra-oculares (humor vítreo e humor aquoso) de pacientes com toxoplasmose ocular, na cidade de Belém, PA

OpenAIRE

Carmo,Ediclei Lima do; Almeida,Edmundo Frota; Bichara,Cléa Nazaré; Póvoa,Marinete Marins

2005-01-01

Foi realizada pesquisa de anticorpos IgG, IgM e IgA anti-Toxoplasma gondii no soro e fluidos intra-oculares (humor aquoso e vítreo) de pacientes com toxoplasmose ocular. A partir dos resultados obtidos verificou-se que anticorpos IgG e IgA intraocular anti-Toxoplasma gondii podem vir a ser importantes marcadores no diagnóstico de toxoplasmose ocular.

Prevalence of Toxoplasma gondii and potentially zoonotic helminths in wild boars (Sus scrofa hunted in central Italy

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Roberto Amerigo Papini

2018-03-01

Full Text Available Our aim was to evaluate the risk of human toxoplasmosis via meat consumption from wild boars by estimating the seroprevalence of Toxoplasma gondii in animals hunted in central Italy. Using a modified agglutination test, 213 sera from wild boars were examined for anti-Toxoplasma IgG antibodies. Diaphragm samples (n=65 from seropositive and seronegative animals were tested by nested-PCR to detect T. gondii DNA. Toxoplasma DNA from diaphragms was genotyped by PCR-RFLP using 12 genetic markers. Moreover, the aim of the study was also to identify helminth infections of wild boars in the selected area and to evaluate their hazard for humans. Examination of sera revealed a seroprevalence of 12.2%. Only one T. gondii strain could be genotyped from a seropositive animal and PCR-RFLP revealed that it belonged to type II. Analysis of 50 samples of faeces and 32 small intestines revealed that 78% and 15.6% of the samples harboured parasites, respectively, with the occurrence of parasites potentially dangerous for humans. These latter included Ascaris suum, Macracanthorhynchus hirudinaceus, Trichuris suis, and Metastrongylus spp. A significant association was found between coprological positivity and male sex. These results indicate that T. gondii infection may be present in wild boar tissues and consumption of undercooked or raw wild boar meat may expose humans to risk of toxoplasmosis in the study area. Furthermore, the study highlights that wild boars are hosts of helminths of veterinary and medical importance transmissible to pigs and humans.

Anti-Toxoplasma Activity of 2-(Naphthalene-2-γlthiol-1H Indole.

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Qasem Asgari

2015-06-01

Full Text Available This study was undertaken to evaluate the viability, infectivity and immunity of Toxoplasma gondii tachyzoites exposed to 2-(naphthalene-2-ylthio-1H-indole.Tachyzoites of RH strain were incubated in various concentrations of 2-(naphthalene-2-ylthio-1H-indole (25-800 μM for 1.5 hours. Then, they were stained by PI and analyzed by Fluorescence-activated cell sorting (FACS. To evaluate the infectivity, the tachyzoites exposed to the different concentrations of the compound were inoculated to 10 BALB/c mice groups. For Control, parasites exposed to DMSO (0.2% v/v were also intraperitoneally inoculated into two groups of mice. The immunity of the exposed tachyzoites was evaluated by inoculation of the naïve parasite to the survived mice.The LD50 of 2-(naphthalene-2-ylthio-1H-indole was 57 μmol. The longevity of mice was dose dependent. Five mice out of group 400μmol and 3 out of group 800μmol showed immunization to the parasite.Our findings demonstrated the toxoplasmocidal activity of the compound. The presence of a well-organized transporter mechanism for indole compounds within the parasite in conjunction with several effective mechanisms of these compounds on Toxoplasma viability would open a window for production of new drugs and vaccines.

Antigen processing and remodeling of the endosomal pathway: requirements for antigen cross-presentation.

Science.gov (United States)

Compeer, Ewoud Bernardus; Flinsenberg, Thijs Willem Hendrik; van der Grein, Susanna Geertje; Boes, Marianne

2012-01-01

Cross-presentation of endocytosed antigen as peptide/class I major histocompatibility complex complexes plays a central role in the elicitation of CD8(+) T cell clones that mediate anti-viral and anti-tumor immune responses. While it has been clear that there are specific subsets of professional antigen presenting cells capable of antigen cross-presentation, identification of mechanisms involved is still ongoing. Especially amongst dendritic cells (DC), there are specialized subsets that are highly proficient at antigen cross-presentation. We here present a focused survey on the cell biological processes in the endosomal pathway that support antigen cross-presentation. This review highlights DC-intrinsic mechanisms that facilitate the cross-presentation of endocytosed antigen, including receptor-mediated uptake, maturation-induced endosomal sorting of membrane proteins, dynamic remodeling of endosomal structures and cell surface-directed endosomal trafficking. We will conclude with the description of pathogen-induced deviation of endosomal processing, and discuss how immune evasion strategies pertaining endosomal trafficking may preclude antigen cross-presentation.

Antigen processing and remodeling of the endosomal pathway: requirements for antigen cross-presentation.

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Ewoud Bernardus Compeer

2012-03-01

Full Text Available The cross-presentation of endocytosed antigen as peptide/class I MHC complexes plays a central role in the elicitation of CD8+ T cell clones that mediate anti-viral and anti-tumor immune responses. While it has been clear that there are specific subsets of professional antigen presenting cells (APC capable of antigen cross-presentation, description of mechanisms involved is still ongoing. Especially amongst dendritic cells (DC, there are specialized subsets that are highly proficient at antigen cross-presentation. We here present a focused survey on the cell biological processes in the endosomal pathway that support antigen cross-presentation. This review highlight DC-intrinsic mechanisms that facilitate the cross-presentation of endocytosed antigen, including receptor-mediated uptake, recycling and maturation including the sorting of membrane proteins, dynamic remodeling of endosomal structures and cell-surface directed endosomal trafficking. We will conclude with description of pathogen-induced deviation of endosomal processing, and discuss how immune evasion strategies pertaining endosomal trafficking may preclude antigen cross-presentation.

Platelet lysate embedded scaffolds for skin regeneration.

Science.gov (United States)

Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Ferrari, Franca; Mori, Michela; Cervio, Marila; Riva, Federica; Liakos, Ioannis; Athanassiou, Athanassia; Saporito, Francesca; Marini, Lara; Caramella, Carla

2015-04-01

The work presents the development of acellular scaffolds extemporaneously embedded with platelet lysate (PL), as an innovative approach in the field of tissue regeneration/reparation. PL embedded scaffolds should have a tridimensional architecture to support cell migration and growth, in order to restore skin integrity. For this reason, chondroitin sulfate (CS) was associated with sodium alginate (SA) to prepare highly porous systems. The developed scaffolds were characterized for chemical stability to γ-radiation, morphology, hydration and mechanical properties. Moreover, the capability of fibroblasts and endothelial cells to populate the scaffold was evaluated by means of proliferation test 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and confocal laser scanning microscopy study. The scaffolds, not altered by sterilization, were characterized by limited swelling and high flexibility, by foam-like structure with bubbles that formed a high surface area and irregular texture suitable for cell adhesion. Cell growth and scaffold population were evident on the bubble surface, where the cells appeared anchored to the scaffold structure. Scaffold network based on CS and SA demonstrated to be an effective support to enhance and to allow fibroblasts and endothelial cells (human umbilical vein endothelial cells, HUVEC) adhesion and proliferation. In particular, it could be hypothesized that cell adhesion was facilitated by the synergic effect of PL and CS. Although further in vivo evaluation is needed, on the basis of in vitro results, PL embedded scaffolds seem promising systems for skin wound healing.

[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.

MYR1-Dependent Effectors Are the Major Drivers of a Host Cell's Early Response to Toxoplasma, Including Counteracting MYR1-Independent Effects.

Science.gov (United States)

Naor, Adit; Panas, Michael W; Marino, Nicole; Coffey, Michael J; Tonkin, Christopher J; Boothroyd, John C

2018-04-03

The obligate intracellular parasite Toxoplasma gondii controls its host cell from within the parasitophorous vacuole (PV) by using a number of diverse effector proteins, a subset of which require the aspartyl protease 5 enzyme (ASP5) and/or the recently discovered MYR1 protein to cross the PV membrane. To examine the impact these effectors have in the context of the entirety of the host response to Toxoplasma , we used RNA-Seq to analyze the transcriptome expression profiles of human foreskin fibroblasts infected with wild-type RH (RH-WT), RHΔ myr1 , and RHΔ asp5 tachyzoites. Interestingly, the majority of the differentially regulated genes responding to Toxoplasma infection are MYR1 dependent. A subset of MYR1 responses were ASP5 independent, and MYR1 function did not require ASP5 cleavage, suggesting the export of some effectors requires only MYR1. Gene set enrichment analysis of MYR1-dependent host responses suggests an upregulation of E2F transcription factors and the cell cycle and a downregulation related to interferon signaling, among numerous others. Most surprisingly, "hidden" responses arising in RHΔ myr1 - but not RH-WT-infected host cells indicate counterbalancing actions of MYR1-dependent and -independent activities. The host genes and gene sets revealed here to be MYR1 dependent provide new insight into the parasite's ability to co-opt host cell functions. IMPORTANCE Toxoplasma gondii is unique in its ability to successfully invade and replicate in a broad range of host species and cells within those hosts. The complex interplay of effector proteins exported by Toxoplasma is key to its success in co-opting the host cell to create a favorable replicative niche. Here we show that a majority of the transcriptomic effects in tachyzoite-infected cells depend on the activity of a novel translocation system involving MYR1 and that the effectors delivered by this system are part of an intricate interplay of activators and suppressors. Removal of all MYR1

An Optimized Method for Manufacturing a Clinical Scale Dendritic Cell-Based Vaccine for the Treatment of Glioblastoma

Science.gov (United States)

Pogliani, Simona; Pellegatta, Serena; Antozzi, Carlo; Baggi, Fulvio; Gellera, Cinzia; Pollo, Bianca; Parati, Eugenio A.; Finocchiaro, Gaetano; Frigerio, Simona

2012-01-01

Immune-based treatments represent a promising new class of therapy designed to boost the immune system to specifically eradicate malignant cells. Immunotherapy may generate specific anti-tumor immune responses, and dendritic cells (DC), professional antigen-presenting cells, are widely used in experimental cancer immunotherapy. Several reports describe methods for the generation of mature, antigen-pulsed DC for clinical use. Improved quality and standardization are desirable to obtain GMP-compliant protocols. In this study we describe the generation of DC from 31 Glioblastoma (GB) patients starting from their monocytes isolated by immunomagnetic CD14 selection using the CliniMACS® device. Upon differentiation of CD14+ with IL-4 and GM-CSF, DC were induced to maturation with TNF-α, PGE2, IL-1β, and IL-6. Whole tumor lysate was obtained, for the first time, in a closed system using the semi-automated dissociator GentleMACS®. The yield of proteins improved by 130% compared to the manual dissociation method. Interestingly the Mean Fluorescence Intensity for CD83 increased significantly in DC pulsed with “new method” lysate compared to DC pulsed with “classical method” lysate. Our results indicate that immunomagnetic isolation of CD14+ monocytes using the CliniMACS® device and their pulsing with whole tumor lysate proteins is a suitable method for clinical-scale generation of high quality, functional DC under GMP-grade conditions. PMID:23284979

Toxoplasma gondii infection in humans in China

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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.

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.

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...

Life cycle of Hammondia hammondi (Apicomplexa: Sarcocystidae) in cats

Science.gov (United States)

Hammondia hammondi and Toxoplasma gondii are feline coccidian that are morphologically, antigenically, and phylogenitically related. Both parasites multiply asexually and sexually in feline intestinal enterocytes but H. hammondi remains confined to enterocytes whereas T. gondii also parasitizes extr...

Occurrence of Toxoplasma gondii antibodies in Lowland Tapirs (Tapirus terrestris) maintained ex-situ in Brazil and Paraguay

Science.gov (United States)

Exposure to Toxoplasma gondii, by the presence of antibodies to the parasite, was documented in 47 Brazilian tapirs (Tapirus terrestris) maintained ex-situ in 10 Brazilian and in one Paraguayan Institution. One animal had samples collected on two occasions (November 2010 and October 2011), and 19 (4...

Serological study for antibodies to toxoplasma gondii in Jakarta, Indonesia.

Science.gov (United States)

Gandahusada, S

1978-09-01

A total of 280 sera from medical students, laboratory personnel from the University of Indonesia and other persons living in Jakarta were tested for antibodies to Toxoplasma gondii by the indirect hemagglutination test. Antibody titers equal to or greater than 1:256 were considered positive and were detected in 35 or 12.5% of the persons tested. The sero-positivity rates were not significant between 178 males (13.5%) and 102 females (10.8%) but were significantly different between persons of Indonesian ancestry (14.3%) and those of Chinese ancestry (2.3%). No correlation could be found between ownership of domestic cats and eating habits and positive titers.

Studies on antigenic cross-reactivity of Trichuris ovis with host mucosal antigens in goat

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Gautam Patra

2015-12-01

Full Text Available Objective: To ascertain whether immunodominant antigens of Trichuris ovis might share and cross react with host molecule. Methods: Two crude protein preparations from anterior and posterior parts of Trichuris ovis were characterized along with host mucosal antigen by double immunodiffusion, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting technique. Conventional scanning electron microscopy was performed as per standard procedure. Results: Sharp and distinct bands of three antigens have been found in double immunodiffusion using hyperimmune serum raised in rabbit indicating the presence of specific antibody against each antigen. All three antigens have shown major and minor bands with molecular weight ranging from 15 to 110 kDa during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Conclusions: The antigenic cross-reactivity was thought to result from shared antigens. The existence of paracloacal papillae found in the anterior part of the male was not a unique feature for species differentiation.

Solid phase radioimmunoassay for detection of serum autoantibodies in systemic lupus erythematosus

Energy Technology Data Exchange (ETDEWEB)

Smith, K O; Harrington, J T; Gehle, W D

1977-03-01

Solid phase radioimmunoassay (RIA) methods for measuring autoantibodies in systemic lupus erythematosus (SLE) patients' serum were developed to improve the sensitvity and quantitative precision of the determinations. Two mechanical systems were studied: (1) acetone fixed cell monolayers in glass tubes and (2) antigen coated plastic beads. Both systems were senssitive and reproducible. The most sensitive, versatile system involves the coating of the plastic beads with nuclear antigen(s), incubation overnight with sera and labelling with /sup 125/I conjugated antihuman globulin. Linear binding of this radioactive tag is obtained over a wide range of SLE serum dilutions and the slopes of the serum dilution titration curves are almost identical for all SLE patients' sera tested. Therefore, a standard titration curve can be constructed from the results with a positive serum, and end-point dilutions of unknown sera estimated from results obtained with a single serum dilution. Alternatively, binding ratios of unknown sera can be usefully compared at fixed dilutions with standard positive and negative sera. For example, high binding ratios (>3.0) were obtained with 19/20 SLE sera and 0/20 control sera. Antigens used in these systems include crude, whole-cell lysates and lysates from purified nuclei.

Toxoplasma gondii infection in the mountain hare (Lepus timidus) and domestic rabbit (Oryctolagus cuniculus). II. Early immune reactions

DEFF Research Database (Denmark)

Gustafsson, K.; Wattrang, E.; Fossum, C.

1997-01-01

As already reported, the mountain hare is much more susceptible than the domestic rabbit to oral inoculation with Toxoplasma gondii, as judged by pathological changes and dissemination of parasites within the body. In the present paper, further interspecies variations are reported. Concentrations...

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

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.

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.

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...

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.

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

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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

Chlorphenesin: an antigen-associated immunosuppressant.

Science.gov (United States)

Whang, H Y; Neter, E

1970-07-01

Chlorphenesin (3-p-chlorophenoxy-1,2-propanediol), when injected intravenously together with either of two common bacterial antigens, inhibits the antibody response of the rabbit. The antigens studied are those common to Enterobacteriaceae and to gram-positive bacteria. The immunosuppression is contingent upon incubation of chlorphenesin and antigen in vitro prior to administration, since separate injection of antigen and inhibitor or of mixtures without prior incubation yields undiminished antibody response. Chlorphenesin, as shown by hemagglutination-inhibition tests, does not alter the antigenic determinants, because antibody neutralization occurs in the presence or absence of the drug. The immunosuppressive effect is reversible, since precipitation of chlorphenesin at 4 C substantially restores immunogenicity. Animals immunized with antigen-drug mixtures, which fail to respond with significant antibody production, nonetheless are immunologically primed. It is concluded that chlorphenesin represents another example of antigen-associated immunosuppressants.

UNC93B1 mediates host resistance to infection with Toxoplasma gondii.

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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.

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.

Clinical and Immunological Effects in Patients with Advanced Non-Small Cell Lung-Cancer after Vaccination with Dendritic Cells Exposed to an Allogeneic Tumor Cell Lysate*

DEFF Research Database (Denmark)

Engell-Noerregaard, Lotte; Kvistborg, Pia; Zocca, Mai-Britt

2013-01-01

Background: We evaluated the clinical and immunological effects of dendritic cell (DC) vaccination of patients with NSCLC. Autologous DCs were pulsed with a MAGE containing allogeneic melanoma cell lysate (MelCancerVac®, Dandrit Biotech, Copenhagen, Denmark). Imiquimod cream, proleukin and celeco......Background: We evaluated the clinical and immunological effects of dendritic cell (DC) vaccination of patients with NSCLC. Autologous DCs were pulsed with a MAGE containing allogeneic melanoma cell lysate (MelCancerVac®, Dandrit Biotech, Copenhagen, Denmark). Imiquimod cream, proleukin...... and celecoxib were used as adjuvants to the vaccines. The objective of the study was to evaluate specific T cell response in vitro by IFN EliSpot. Secondary objec- tives were overall survival, response and quality of life (QoL). Results: Twenty-two patients initiated the vaccination program consisting of ten...

Carcinoembryonic antigen (CEA)

International Nuclear Information System (INIS)

Ephraim, K.H.; Cox, P.H.; Hamer, C.J.A. v.d.; Berends, W.; Delhez, H.

1977-01-01

The carcinoembryonic antigen (CEA) is a complex of antigen determinants and also the carrier of these determinants. Chemically it is a glycoprotein. Its occurrence in blood serum or urine is correlated with malignant disease. Several radioimmunoassays (RIA) have been developed, one by Hoffmann-Laroche and one by the Rotterdam Radiotherapeutic Institute. Both methods and the Hoffmann assay kit are tested. Specifications are given for isolation of the antigen, preparation of the antiserum, and the execution of the RIA. Biochemical and clinical aspects are discussed

[Detection of Toxoplasma gondii infection of sheep slaughtered in the governorate of Sousse on the occasion of the Muslim sacrifice feast (Eid Al-Adha) and analysis of risk factors].

Science.gov (United States)

Khayeche, M; Mhadhbi, M; Gharbi, M; Nasfi, I; Darghouth, M A

2014-02-01

During the Muslim feast of Sacrifice (Eid Al-Adha), DNA of Toxoplasma gondii was screened in the heart apex of 70 sheep belonging to different households in Sousse region (North-East of Tunisia) by nested PCR.DNA of T. gondii was identified in 5.7% of the samples. To study different risk factors of Toxoplasma gondii transmission that can be present especially for this occasion, a questionnaire was established. It revealed that the majority of households (92.9%) slaughtered a sheep aged less than 1 year old. Moreover, 2% of the study population consumed undercooked meat. This study showed also that the majority of meat handlers did not respect the hygiene rules, since 91% of them did not wash their hands after handling and before preparing or consuming food. The presence of the definitive host (cats) is considered among the factors that increase the risk of Toxoplasma infection. It was recorded in 14% of the households with the presence of elements that increases the risk as defecating in the house and eating raw meat during Eid Al-Adha feast. Our results show that the risk factors of Toxoplasma infection increase during this occasion; it requires the establishment of a sanitary education programme during this feast.

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.

Seroprevalence of Toxoplasma gondii infection in cats from Curitiba, Paraná, Brazil Soroprevalência de infecção anti-Toxoplasma gondii em gatos domésticos de Curitiba, Paraná, Brasil

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Marúcia de Andrade Cruz

2011-09-01

Full Text Available Toxoplasmosis is a worldwide zoonosis caused by the protozoa Toxoplasma gondii which infects all warm-blood vertebrates. This study aimed to assess the seroprevalence of anti-Toxoplasma gondii antibodies in a population of domestic cats seen at a major cat-only veterinary clinic in Curitiba, Paraná State, Southern Brazil. Serum samples were processed by indirect immunofluorescence assay (IIFA for the detection of IgG. Antibody titers were found in 16.3% (46/282 of sera analyzed, with titers to T. gondii of 16 in eight cats, 64 in 23 cats, 256 in 14 cats and 1024 in one cat. Statistical differences were not found regarding the association with age, gender and different areas of the city (p > 0.05. No significant differences were found in any variable when comparing seropositivity with potential risk factors. The seroprevalence was relatively lower when compared to other Brazilian regions, probably due to the fact that the cats studied were owned, domiciled with restricted dietary habits based on processed foods, restricted access to the street and no prey access. In conclusion, low feline toxoplasmosis seroprevalence may be associated to owned cats due to adequate dietary care and restricted outdoor access, as well as low local environmental exposure.A toxoplasmose é uma zoonose de distribuição mundial, causada pelo protozoário Toxoplasma gondii que infecta os vertebrados de sangue quente. Este estudo objetiva estabelecer a prevalência de anticorpos anti-Toxoplasma gondii e o estudo de associação em uma população de gatos domésticos atendidos em uma clínica veterinária exclusiva de gatos localizada em Curitiba, estado do Paraná, Brasil. As amostras de soro foram obtidas e processadas pela reação de imunofluorescência indireta IgG. Títulos de anticorpos foram encontrados em 46/282 (16,3% das amostras analisadas, com título de 16 em oito gatos, 64 em 23, 256 em 14 e 1024 em um gato. Diferenças estatísticas não foram

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 ...

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...

Human Platelet Lysate as a Replacement for Fetal Bovine Serum in Limbal Stem Cell Therapy.

Science.gov (United States)

Suri, Kunal; Gong, Hwee K; Yuan, Ching; Kaufman, Stephen C

2016-10-01

To evaluate the use of human platelet lysate (HPL) as an alternative supplement for limbal explant culture. Culture media were prepared using either 10% pooled HPL (PHPL), single donor HPL, or fetal bovine serum (FBS). Limbal tissues, obtained from the Minnesota Lions Eye Bank, were cultured in each medium on plastic plates or on denuded amniotic membrane (AM). Immunofluorescence staining was performed for ABCG2, tumor protein p63α, and cytokeratin 3 (K3). Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to evaluate the expression of ABCG2 and p63. Limbal explants grown in each medium were labeled with bromodeoxyuridine (BrdU) to assess the proliferative capacity in each medium. Concentration of growth factors including epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), transforming growth factor-β (TGF-β), and platelet derived growth factor (PDGF) in HPL and PHPL was compared to that in human serum (HS). Immunofluorescence staining on AM showed prominent expression of ABCG2, p63α but sparse expression of K3 in HPL and PHPL supplemented medium. Real time-PCR showed 1.7 fold higher expression of ABCG2 in PHPL supplemented medium (p = 0.03), and similar expression of p63 in HPL and PHPL supplemented medium compared to FBS medium. The proliferation assay showed that LSCs retained their proliferative potential in HPL supplemented medium. Higher concentration of growth factors were found in HPL, compared to HS. Human platelet lysate has higher concentration of grown factors and is effective in maintaining growth and stem cell phenotype of corneal limbal explant cultures.

Antigenic determinants and functional domains in core antigen and e antigen from hepatitis B virus

International Nuclear Information System (INIS)

Salfeld, J.; Pfaff, E.; Noah, M.; Schaller, H.

1989-01-01

The precore/core gene of hepatitis B virus directs the synthesis of two polypeptides, the 21-kilodalton subunit (p21c) forming the viral nucleocapsid (serologically defined as core antigen [HBcAg]) and a secreted processed protein (p17e, serologically defined as HBe antigen [HBeAg]). Although most of their primary amino acid sequences are identical, HBcAg and HBeAg display different antigenic properties that are widely used in hepatitis B virus diagnosis. To locate and to characterize the corresponding determinants, segments of the core gene were expressed in Escherichia coli and probed with a panel of polyclonal or monoclonal antibodies in radioimmunoassays or enzyme-linked immunosorbent assays, Western blots, and competition assays. Three distinct major determinants were characterized. It is postulated that HBcAg and HBeAg share common basic three-dimensional structure exposing the common linear determinant HBe1 but that they differ in the presentation of two conformational determinants that are either introduced (HBc) or masked (HBe2) in the assembled core. The simultaneous presentation of HBe1 and HBc, two distinctly different antigenic determinants with overlapping amino acid sequences, is interpreted to indicate the presence of slightly differently folded, stable conformational states of p21c in the hepatitis virus nucleocapsid

The Orphan Nuclear Receptor TLX Is an Enhancer of STAT1-Mediated Transcription and Immunity to Toxoplasma gondii.

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Daniel P Beiting

2015-07-01

Full Text Available The protozoan parasite, Toxoplasma, like many intracellular pathogens, suppresses interferon gamma (IFN-γ-induced signal transducer and activator of transcription 1 (STAT1 activity. We exploited this well-defined host-pathogen interaction as the basis for a high-throughput screen, identifying nine transcription factors that enhance STAT1 function in the nucleus, including the orphan nuclear hormone receptor TLX. Expression profiling revealed that upon IFN-γ treatment TLX enhances the output of a subset of IFN-γ target genes, which we found is dependent on TLX binding at those loci. Moreover, infection of TLX deficient mice with the intracellular parasite Toxoplasma results in impaired production of the STAT1-dependent cytokine interleukin-12 by dendritic cells and increased parasite burden in the brain during chronic infection. These results demonstrate a previously unrecognized role for this orphan nuclear hormone receptor in regulating STAT1 signaling and host defense and reveal that STAT1 activity can be modulated in a context-specific manner by such "modifiers."

The Orphan Nuclear Receptor TLX Is an Enhancer of STAT1-Mediated Transcription and Immunity to Toxoplasma gondii.

Science.gov (United States)

Beiting, Daniel P; Hidano, Shinya; Baggs, Julie E; Geskes, Jeanne M; Fang, Qun; Wherry, E John; Hunter, Christopher A; Roos, David S; Cherry, Sara

2015-07-01

The protozoan parasite, Toxoplasma, like many intracellular pathogens, suppresses interferon gamma (IFN-γ)-induced signal transducer and activator of transcription 1 (STAT1) activity. We exploited this well-defined host-pathogen interaction as the basis for a high-throughput screen, identifying nine transcription factors that enhance STAT1 function in the nucleus, including the orphan nuclear hormone receptor TLX. Expression profiling revealed that upon IFN-γ treatment TLX enhances the output of a subset of IFN-γ target genes, which we found is dependent on TLX binding at those loci. Moreover, infection of TLX deficient mice with the intracellular parasite Toxoplasma results in impaired production of the STAT1-dependent cytokine interleukin-12 by dendritic cells and increased parasite burden in the brain during chronic infection. These results demonstrate a previously unrecognized role for this orphan nuclear hormone receptor in regulating STAT1 signaling and host defense and reveal that STAT1 activity can be modulated in a context-specific manner by such "modifiers."

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 ...

Hallazgo de antígenos en un tumor murino espontáneo no inmunogénico mediante el uso de una vacuna basada en células dendríticas Unveiling antigens in a non-immunogenic spontaneous murine tumor using a dendritic cell-based vaccine

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Verónica L. Reffo

2008-08-01

absence of tumor antigens or to the existence of tolerogenic mechanisms preventing such antigens from initiating an antitumor immune response. We have used two murine tumors -a non-immunogenic spontaneous lymphoma (LB and a strongly immunogenic methylcholanthrene-induced fibrosarcoma (MC-C- together with a vaccination strategy based on the inoculation of dendritic cells (DC loaded with a tumor lysate. When DC were pulsed with LB lysate (DC+LB, no maturation of DC was achieved in vitro and no protection against LB implants after DC+LB inoculation was observed in vivo. On the other hand, when DC were pulsed with MC-C lysate (DC+MC-C, maturation of DC was observed along with a strong protection against MC-C implants after DC+MC-C inoculaton. Finally, when DC were pulsed with both LB and MC-C lysates (DC+LB+MC-C, maturation of DC and protection against LB implants were achieved. Since no immune cross reaction between MC-C and LB was ever observed, the most likely interpretation is that LB bears specific tumor antigens but lacks other signals to achieve DC maturation. These signals would be provided by MC-C which would enable DC to mature and to initiate an effective anti-LB immune response.

Evaluation of four indirect ELISA systems for the detection of trypanosomal antibodies in bovine serum

International Nuclear Information System (INIS)

Ndamkou, C.N.; Yomo, J.P.

2000-01-01

Four indirect-ELISA systems developed by the Joint FAO/IAEA Division for the detection of trypanosomal antibodies in bovine serum were evaluated in the field. Internal quality control data obtained were good showing that pre-coating plates with antigen increase the robustness of the assay and contribute to its standardisation. ELISA systems derived from Trypanosoma vivax antigen lysates gave a better performance than ELISA systems using T. congolense antigens. Sensitivity and specificity corresponding to the highest accuracy were 86-87% and 83-85% respectively. When comparing the two ELISA systems utilising T. vivax antigens, there was no significant difference between native and denatured antigens and diagnostic threshold was higher for denatured antigens. (author)

Comprehensive Evaluation of Toxoplasma gondii VEG and Neospora caninum LIV Genomes with Tachyzoite Stage Transcriptome and Proteome Defines Novel Transcript Features

KAUST Repository

Ramaprasad, Abhinay; Mourier, Tobias; Naeem, Raeece; Malas, Tareq B.; Moussa, Ehab; Panigrahi, Aswini; Vermont, Sarah J.; Otto, Thomas D.; Wastling, Jonathan; Pain, Arnab

2015-01-01

Toxoplasma gondii is an important protozoan parasite that infects all warm-blooded animals and causes opportunistic infections in immuno-compromised humans. Its closest relative, Neospora caninum, is an important veterinary pathogen that causes

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...

Quantitative in vivo analyses reveal calcium-dependent phosphorylation sites and identifies a novel component of the Toxoplasma invasion motor complex.

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Thomas Nebl

2011-09-01

Full Text Available Apicomplexan parasites depend on the invasion of host cells for survival and proliferation. Calcium-dependent signaling pathways appear to be essential for micronemal release and gliding motility, yet the target of activated kinases remains largely unknown. We have characterized calcium-dependent phosphorylation events during Toxoplasma host cell invasion. Stimulation of live tachyzoites with Ca²⁺-mobilizing drugs leads to phosphorylation of numerous parasite proteins, as shown by differential 2-DE display of ³²[P]-labeled protein extracts. Multi-dimensional Protein Identification Technology (MudPIT identified ∼546 phosphorylation sites on over 300 Toxoplasma proteins, including 10 sites on the actomyosin invasion motor. Using a Stable Isotope of Amino Acids in Culture (SILAC-based quantitative LC-MS/MS analyses we monitored changes in the abundance and phosphorylation of the invasion motor complex and defined Ca²⁺-dependent phosphorylation patterns on three of its components--GAP45, MLC1 and MyoA. Furthermore, calcium-dependent phosphorylation of six residues across GAP45, MLC1 and MyoA is correlated with invasion motor activity. By analyzing proteins that appear to associate more strongly with the invasion motor upon calcium stimulation we have also identified a novel 15-kDa Calmodulin-like protein that likely represents the MyoA Essential Light Chain of the Toxoplasma invasion motor. This suggests that invasion motor activity could be regulated not only by phosphorylation but also by the direct binding of calcium ions to this new component.

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 ...

A novel multifunctional oligonucleotide microarray for Toxoplasma gondii

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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

Congenital toxoplasma infection: monthly prenatal screening decreases transmission rate and improves clinical outcome at age 3 years.

Science.gov (United States)

Wallon, M; Peyron, F; Cornu, C; Vinault, S; Abrahamowicz, M; Kopp, C Bonithon; Binquet, C

2013-05-01

Toxoplasma infection during pregnancy exposes the fetus to risks of congenital infection and sequelae that depend heavily on gestational age (GA) at time of infection. Accurate risk estimates by GA are necessary to counsel parents and improve clinical decisions. We analyzed data from pregnant women diagnosed with acute Toxoplasma infection in Lyon (France) from 1987 to 2008 and assessed how the risks of congenital toxoplasmosis and of clinical signs at age 3 years vary depending on GA at the time of maternal infection. Among 2048 mother-infant pairs, 93.2% of mothers received prenatal treatment and 513 (24.7%) fetuses were infected. Because of a significant reduction in risk since 1992 when monthly screening was introduced (59.4% vs 46.6% at 26 GA weeks; P = .038), probabilities of infection were estimated on the basis of maternal infections diagnosed after mid-1992 (n = 1624). Probabilities of congenital infection were <10% for maternal infections before 12 weeks of gestation, rose to 20.0% at 19 weeks, and then continued increasing to 52.3% and almost 70% at 28 and 39 GA weeks, respectively. Because of a significant reduction in risk of clinical signs of congenital toxoplasmosis in infected children born from mothers diagnosed after 1995 when polymerase chain reaction testing on amniotic fluid was initiated (87/794 vs 46/1150; P = .012), probabilities of clinical signs at 3 years were estimated based on 1015 maternal infections diagnosed after 1995 including 207 infected children, with symptoms in 46 (22.2%). These analyses demonstrated that introduction of monthly prenatal screening and improvement in antenatal diagnosis were associated with a significant reduction in the rate of congenital infection and a better outcome at 3 years of age in infected children. Our updated estimates will improve individual management and counseling in areas where genotype II Toxoplasma is predominant.

Molecular diagnosis of toxoplasmosis: value of the buffy coat for the detection of circulating Toxoplasma gondii.

Science.gov (United States)

Brenier-Pinchart, Marie-Pierre; Capderou, Elodie; Bertini, Rose-Laurence; Bailly, Sébastien; Fricker-Hidalgo, Hélène; Varlet-Marie, Emmanuelle; Murat, Jean-Benjamin; Sterkers, Yvon; Touafek, Fériel; Bastien, Patrick; Pelloux, Hervé

2015-08-01

Early detection of Toxoplasma tachyzoites circulating in blood using PCR is recommended for immunosuppressed patients at high risk for disseminated toxoplasmosis. Using a toxoplasmosis mouse model, we show that the sensitivity of detection is higher using buffy coat isolated from a large blood volume than using whole blood for this molecular monitoring. Copyright © 2015 Elsevier Inc. All rights reserved.

Autologous platelet lysate local injections for the treatment of refractory lateral epicondylitis.

Science.gov (United States)

Tan, Xun-xiang; Ju, Hai-yang; Yan, Wei; Jiang, Hong-jiang; Su, Jin-ping; Dong, Hua-jun; Wang, Ling-shuang; Zou, De-bao

2016-01-25

The purpose of this study was to investigate the efficacy and safety of autologous platelet lysate (APL) local injections in reducing pain and improving function in patients with refractory lateral epicondylitis. A total of 56 patients with refractory lateral epicondylitis were enrolled in this study. All the patients received three injections in one course of treatment. Subjective assessments include visual analog scale (VAS) pain score and Mayo elbow score before injection (baseline) and at 1, 6, and 12 months after injection. Significant differences were observed in VAS and Mayo scores at baseline and at 1, 6, and 12 months after injection. Overall, the injections of APL improved local symptoms and all the patients recovered to normal elbow function with 12 months follow-up. Local injections of APL resulted in favorable clinical outcomes for the treatment of lateral epicondylitis. APL could be clinically effective in the treatment of lateral epicondylitis.

Prevalence and risk factors for Toxoplasma gondii infection in certified and non-certified pig breeding farms in the Toledo microregion, PR, Brazil Prevalência e fatores de risco para a infecção pelo Toxoplasma gondii em granjas de reprodutores suídeos certificados ou não da microregião de Toledo, PR, Brasil

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Piassa Franciele Rossandra

2010-09-01

Full Text Available Toxoplasma gondii infection has been diagnosed in pigs all over the world. Economical losses are generally related to reproductive disorders. Toxoplasma infection is also a matter of public health because tissue cysts of the parasite may remain in pork and pork products, and become sources of human infection. The objective of this study was to evaluate the frequency and risk factors associated with Toxoplasma infection in certified and non-certified pig breeding farms in the Toledo microregion, in the State of Paraná, Brazil which includes the cities of Toledo, Nova Santa Rosa, Sao José das Palmeiras and Sao Pedro do Iguaçu. Relative frequency of infection was 13.4%, independently of the type of farm. Logistic regression analysis showed that the following factors were associated with infection: absence of workers exclusive for each area of the farm, access of other animals to feeders and drinkers, lack of lids in drinkers, lack of rodent control measures, mean piglet number and weight at weaning per female.A infecção pelo Toxoplasma gondii tem sido diagnosticada em suínos em todo o mundo. Perdas econômicas geralmente estão relacionadas a distúrbios reprodutivos. A infecção pelo Toxoplasma tem também importância em saúde pública, já que cistos teciduais do parasito podem persistir na carne e subprodutos oriundos de suínos, que servirão de fontes de infecção para o ser humano. O objetivo deste trabalho foi verificar a frequência e os fatores de risco associados à infecção pelo Toxoplasma em granjas de reprodutores suídeos certificados ou não da microrregião de Toledo, no Paraná, que inclui os municípios de Toledo, Nova Santa Rosa, São José das Palmeiras e São Pedro do Iguaçú. A frequência relativa de infecção foi 13,4%, sem diferença com o tipo de granja. A análise de regressão logística demonstrou os seguintes fatores associados à infecção: não utilização de funcionários separados por área da

Potential radioimmunoassay system for detection of Hanganutziu-Deicher type heterophile antigen(s) and antibodies in tissues and fluids

Energy Technology Data Exchange (ETDEWEB)

Mukuria, J C; Naiki, Masaharu; Hashimoto, Masato; Nishiura, Katsumi; Okabe, Masahiro; Kato, Shiro

1985-06-12

A relatively simple, specific and sensitive radioimmunoassay system has been developed for the detection of heterophile Hanganutziu-Deicher (H-D) antigen(s) and antibodies. The SVI-labeled H-D antigen-active molecule used for the assay is a bovine erythrocyte major glycoprotein previously found to have a strong H-D antigen potency. Different H-D antigen-active molecules were compared for heterophile H-D antigen potency. Eight different lung cancer tissues were assayed for H-D antigen. The sera from the 8 lung cancer patients were also screened by ELISA and RIA in an attmept to correlate expression of H-D antigen on tissues with elevation of H-D antibodies.

Exosomes: novel effectors of human platelet lysate activity

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E Torreggiani

2014-09-01

Full Text Available Despite the popularity of platelet-rich plasma (PRP and platelet lysate (PL in orthopaedic practice, the mechanism of action and the effectiveness of these therapeutic tools are still controversial. So far, the activity of PRP and PL has been associated with different growth factors (GF released during platelet degranulation. This study, for the first time, identifies exosomes, nanosized vesicles released in the extracellular compartment by a number of elements, including platelets, as one of the effectors of PL activity. Exosomes were isolated from human PL by differential ultracentrifugation, and analysed by electron microscopy and Western blotting. Bone marrow stromal cells (MSC treated with three different exosome concentrations (0.6 μg, 5 μg and 50 μg showed a significant, dose-dependent increase in cell proliferation and migration compared to the control. In addition, osteogenic differentiation assays demonstrated that exosome concentration differently affected the ability of MSC to deposit mineralised matrix. Finally, the analysis of exosome protein content revealed a higher amount of basic fibroblast growth factor (bFGF, vascular endothelial growth factor (VEGF, platelet-derived growth factor (PDGF-BB and transforming growth factor beta 1 (TGF-β1 as compared to PL. In regards to RNA content, an enrichment of small RNAs in exosomes as compared to donor platelets has been found. These results suggest that exosomes consistently contribute to PL activity and could represent an advantageous nanodelivery system for cell-free regeneration therapies.

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...

His-tag ELISA for the detection of humoral tumor-specific immunity

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Disis Mary L

2008-05-01

Full Text Available Abstract Background The application of high throughput molecular techniques such as SEREX are resulting in the identification of a multitude of tumor associated antigens. As newly identified antigens are incorporated into a variety of clinical trials, standardization of immunologic monitoring methods becomes increasingly important. We questioned whether mammalian cell expression of a histadine-linked human protein could be used to produce antigen suitable for detecting tumor-specific humoral immunity and whether such an assay could be amenable to standardization for clinical use. Methods We designed a his-tagged capture ELISA based on lysate from genetically engineered CHO cells for detection of antibodies to insulin-like growth factor binding protein 2, a novel tumor antigen. We performed technical and preliminary clinical validation studies, including comparison to a standard indirect ELISA based on commercially prepared recombinant antigen. Results The his-tagged capture ELISA could be standardized. Precision experiments resulted in CVs 2 values of 0.99. In comparison to Western blot analysis, his-tag and indirect ELISA accurately identified 88% and 93% of samples, respectively. Sample concordance between capture and indirect assays was highly significant (p = 0.003. Furthermore, significantly greater levels of IGFBP-2 antibody immunity were found in cancer patients compared to normal controls (p = 0.008. Conclusion A genetically engineered cell lysate based ELISA can be amenable to standardization and can detect increased levels of antibody immunity to tumor-associated antigen in cancer patients compared to non tumor-bearing healthy controls.

Toxoplasma DJ-1 Regulates Organelle Secretion by a Direct Interaction with Calcium-Dependent Protein Kinase 1

Science.gov (United States)

Child, Matthew A.; Garland, Megan; Foe, Ian; Madzelan, Peter; Treeck, Moritz; van der Linden, Wouter A.; Oresic Bender, Kristina; Weerapana, Eranthie; Wilson, Mark A.; Boothroyd, John C.; Reese, Michael L.

2017-01-01

ABSTRACT Human DJ-1 is a highly conserved and yet functionally enigmatic protein associated with a heritable form of Parkinson’s disease. It has been suggested to be a redox-dependent regulatory scaffold, binding to proteins to modulate their function. Here we present the X-ray crystal structure of the Toxoplasma orthologue Toxoplasma gondii DJ-1 (TgDJ-1) at 2.1-Å resolution and show that it directly associates with calcium-dependent protein kinase 1 (CDPK1). The TgDJ-1 structure identifies an orthologously conserved arginine dyad that acts as a phospho-gatekeeper motif to control complex formation. We determined that the binding of TgDJ-1 to CDPK1 is sensitive to oxidation and calcium, and that this interaction potentiates CDPK1 kinase activity. Finally, we show that genetic deletion of TgDJ-1 results in upregulation of CDPK1 expression and that disruption of the CDPK1/TgDJ-1 complex in vivo prevents normal exocytosis of parasite virulence-associated organelles called micronemes. Overall, our data suggest that TgDJ-1 functions as a noncanonical kinase-regulatory scaffold that integrates multiple intracellular signals to tune microneme exocytosis in T. gondii. PMID:28246362

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.

Human cord blood-derived platelet lysate enhances the therapeutic activity of adipose-derived mesenchymal stromal cells isolated from Crohn's disease patients in a mouse model of colitis.

Science.gov (United States)

Forte, Dorian; Ciciarello, Marilena; Valerii, Maria Chiara; De Fazio, Luigia; Cavazza, Elena; Giordano, Rosaria; Parazzi, Valentina; Lazzari, Lorenza; Laureti, Silvio; Rizzello, Fernando; Cavo, Michele; Curti, Antonio; Lemoli, Roberto M; Spisni, Enzo; Catani, Lucia

2015-09-09

Due to their immunomodulatory properties, mesenchymal stromal cells (MSCs) have been used for auto-immune disease treatment. Crohn disease (CD) and ulcerative colitis are two major inflammatory bowel diseases (IBDs), resulting from pathological immune responses to environmental or microbial antigens. Preclinical and clinical studies have suggested that MSC-based cellular therapy hold promising potential for IBD treatment. However, open issues include the selection of the proper cell dose, the source and the optimal route of administration of MSCs for more effective results. Platelet lysate has gained clinical interest due to its efficacy in accelerating wound healing. Thus, we propose to combine the administration of MSCs with a human umbilical cord blood-derived platelet lysate (hCBPL) as a novel strategy to improve MSC-based therapy for IBD resolution. Colitis was induced in 8-week-old C57BL/6J mice by daily oral administration of dextran sulphate sodium (DSS) (1.5 % w/v in tap water) for 9 days. MSCs were isolated from adipose tissue of CD patients (adCD-MSCs), expanded in proliferation medium, resuspended in hCBPL or PBS and administrated via enema for three times (1 × 10(6) cells/mouse/time) every other day starting on day +7 from DSS induction. The colitis evolution was evaluated by daily monitoring of body weight, stool consistency and bleeding. Histopathological analysis was performed. Inflammatory cytokine plasma levels were determined. adCD-MSCs stained with lipophilic membrane dye Nile Red, were injected in DSS mice as described above. Colon section of mice sacrificed 24 hours after last cell administration, were analyzed by confocal microscopy. We found that adCD-MSCs could be easily isolated and expanded from CD patients. Upon injection, adCD-MSCs exerted a therapeutic effect on DSS-induced colitis. Moreover, hCBPL increased adCD-MSCs efficacy by significantly reducing colitis scores, extension of the colon inflamed area and plasma levels of

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

NARCIS (Netherlands)

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

2012-01-01

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

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.

Survey of the parasite Toxoplasma gondii in human consumed ovine meat in Tunis City.

Directory of Open Access Journals (Sweden)

Sonia Boughattas

Full Text Available Toxoplasmosis has been recognized as parasitic zoonosis with the highest human incidence. The human infection by the parasite can lead to severe clinical manifestations in congenital toxoplasmosis and immunocompromised patients. Contamination occurs mainly by foodborne ways especially consumption of raw or undercooked meat. In contrast to other foodborne infections, toxoplasmosis is a chronic infection which would make its economic and social impact much higher than even previously anticipated. Ovine meat was advanced as a major risk factor, so we investigated its parasite survey, under natural conditions. Serological MAT technique and touchdown PCR approaches were used for prevalence determination of the parasite in slaughtered sheep intended to human consumption in Tunis City. The genotyping was carried by SNPs analysis of SAG3 marker. Anti-Toxoplasma antibodies were present in 38.2% of young sheep and in 73.6% of adult sheep. Molecular detection revealed the contamination of 50% of ewes' tissue. Sequencing and SNPs analysis enabled unambiguous typing of meat isolates and revealed the presence of mixed strains as those previously identified from clinical samples in the same area. Our findings conclude that slaughtered sheep are highly infected, suggesting them as a major risk factor of Toxoplasma gondii transmission by meat consumption. Special aware should target consequently this factor when recommendations have to be established by the health care commanders.

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)

Equine platelet lysate as an alternative to fetal bovine serum in equine mesenchymal stromal cell culture - too much of a good thing?

Science.gov (United States)

Russell, K A; Koch, T G

2016-03-01

Multipotent mesenchymal stromal cells (MSC) are often culture-expanded in vitro. Presently, expansion medium (EM) for MSC is supplemented with fetal bovine serum (FBS). However, increasing cost, variable composition and potential risks associated with bovine antigens call for alternatives. Platelet lysate (PL) has shown promise as an alternative supplement. To determine how equine umbilical cord blood (CB) MSC proliferate in EM enriched with PL or FBS at various concentrations. Randomised dose escalation study. Platelet concentrate was generated from 5 equine whole blood samples through a double centrifugation method and standardised to 1 × 10(12) platelets/l prior to a freeze/thaw cycle to produce PL. Pooled PL or pooled FBS was added to EM at concentrations of 5% to 60%. Proliferation of 4 equine CB-MSC cultures was determined after 4 days using a resazurin semiquantitative assay. Cord blood-MSC proliferated with a dose-dependent response with no significant difference found between PL and FBS up to a 30% concentration. Beyond 30%, proliferation fell in the PL-cultured cells, while continued dose-dependent proliferation was noted in the FBS-cultured cells. Despite reduced cell numbers in high PL concentrations, live/dead staining revealed that adherent cells remained viable. Expansion medium enriched with PL can support short-term equine CB-MSC proliferation at conventional culture concentrations. Based on the unexpected suppression of CB-MSC at higher PL concentrations, an in vivo dose study is indicated to investigate if combinational therapies of CB-MSC and platelet-rich plasma are associated with synergistic or antagonistic effect on CB-MSC function. © 2015 EVJ Ltd.

Oncogenic cancer/testis antigens

DEFF Research Database (Denmark)

Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

2015-01-01

Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

Radioimmunoassays of hidden viral antigens

International Nuclear Information System (INIS)

Neurath, A.R.; Strick, N.; Baker, L.; Krugman, S.

1982-01-01

Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid-phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bound adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure

Detection and dissemination of Toxoplasma gondii in experimentally infected calves, a single test does not tell the whole story.

NARCIS (Netherlands)

Burrells, Alison; Taroda, Alessandra; Opsteegh, Marieke; Schares, Gereon; Benavides, Julio; Dam-Deisz, Cecile; Bartley, Paul M; Chianini, Francesca; Villena, Isabella; van der Giessen, Joke; Innes, Elisabeth A; Katzer, Frank

2018-01-01

Although the detection of Toxoplasma gondii in bovine tissues is rare, beef might be an important source of human infection. The use of molecular techniques, such as magnetic capture qPCR (MC-qPCR), in combination with the gold standard method for isolating the parasite (mouse bioassay), may

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...

Author Details

African Journals Online (AJOL)

Vol 7, No 4 (2017) - Articles Seroprevalence of Toxoplasma gondii and Neospora caninum infections in goats from two Argentinean provinces. Abstract PDF · Vol 8, No 1 (2018) - Articles Lectin binding patterns and immunohistochemical antigen detection in placenta and lungs of Brucella abortus-bovine infected fetuses

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...

Isolation and genetic characterization of viable Toxoplasma gondii from tissues and feces of cats from the central region of China

Science.gov (United States)

Cats are important in the epidemiology of toxoplasmosis because they are the only definitive hosts that excrete environmentally resistant Toxoplasma gondii oocysts. Little is known of feline toxoplasmosis in China and most of the literature is in Chinese. Here we summarized all published reports on ...

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 (...

Leukemia-associated antigens in man.

Science.gov (United States)

Brown, G; Capellaro, D; Greaves, M

1975-12-01

Rabbit antisera raised against acute lymphoblastic leukemia (ALL) cells were used to distinguish ALL from other leukemias, to identify rare leukemia cells in the bone marrow of patients in remission, and to define human leukemia-associated antigens. Antibody binding was studied with the use of immunofluorescence reagents and the analytic capacity of the Fluorescence Activated Cell Sorter-1 (FACS-1). The results indicated that most non-T-cell ALL have three leukemia-associated antigens on their surface which are absent from normal lymphoid cells: 1) an antigen shared with myelocytes, myeloblastic leukemia cells, and fetal liver (hematopoietic) cells; 2) an antigen shared with a subset of intermediate normoblasts in normal bone marrow and fetal liver; and 3) an antigen found thus far only on non-T-cell ALL and in some acute undifferentiated leukemias, which we therefore regard as a strong candidate for a leukemia-specific antigen. These antigens are absent from a subgroup of ALL patients in which the lymphoblasta express T-cell surface markers. Preliminary studies on the bone marrow samples of patients in remission indicated that rare leukemia cells were present in some samples. The implications of these findings with respect to the heterogeneity and cell origin(s) of ALL, its diagnosis, and its potential monitoring during treatment were discussed.

Anvendelse af prostataspecifikt antigen. En oversigt

DEFF Research Database (Denmark)

Brasso, K; Skaarup, P; Roosen, Jens Ulrik

1998-01-01

Since it was first introduced, measurement of prostate specific antigen has gained increasing interest, and prostate specific antigen is regarded as being the best tumour marker available. The antigen lacks cancer specificity, limiting the usefulness in early diagnosis, The use of prostate specific...... antigen in early diagnosis, staging, and in monitoring patients with prostate cancer is reviewed....

The virion N protein of infectious bronchitis virus is more phosphorylated than the N protein from infected cell lysates

International Nuclear Information System (INIS)

Jayaram, Jyothi; Youn, Soonjeon; Collisson, Ellen W.

2005-01-01

Because phosphorylation of the infectious bronchitis virus (IBV) nucleocapsid protein (N) may regulate its multiple roles in viral replication, the dynamics of N phosphorylation were examined. 32 P-orthophosphate labeling and Western blot analyses confirmed that N was the only viral protein that was phosphorylated. Pulse labeling with 32 P-orthophosphate indicated that the IBV N protein was phosphorylated in the virion, as well as at all times during infection in either chicken embryo kidney cells or Vero cells. Pulse-chase analyses followed by immunoprecipitation of IBV N proteins using rabbit anti-IBV N polyclonal antibody demonstrated that the phosphate on the N protein was stable for at least 1 h. Simultaneous labeling with 32 P-orthophosphate and 3 H-leucine identified a 3.5-fold increase in the 32 P: 3 H counts per minute (cpm) ratio of N in the virion as compared to the 32 P: 3 H cpm ratio of N in the cell lysates from chicken embryo kidney cells, whereas in Vero cells the 32 P: 3 H cpm ratio of N from the virion was 10.5-fold greater than the 32 P: 3 H cpm ratio of N from the cell lysates. These studies are consistent with the phosphorylation of the IBV N playing a role in assembly or maturation of the viral particle

Evaluation of human platelet lysate and dimethyl sulfoxide as cryoprotectants for the cryopreservation of human adipose-derived stem cells.

Science.gov (United States)

Wang, Chuan; Xiao, Ran; Cao, Yi-Lin; Yin, Hong-Yu

2017-09-09

Cryopreservation provides an effective technique to maintain the functional properties of human adipose-derived stem cells (ASCs). Dimethylsulfoxide (DMSO) and fetal bovine serum (FBS) are frequently used as cryoprotectants for this purpose. However, the use of DMSO can result in adverse effects and toxic reactions and FBS can introduce risks of viral, prion, zoonose contaminations and evoke immune responses after injection. It is therefore crucial to reduce DMSO concentrations and use serum-free solution in the cryopreservation process. Human platelet lysate (PL) is a promising candidate for use as an alternative to DMSO and FBS. Therefore, in this study, with an aim to identify a cryoprotective agent for ASC cryopreservation, we determined the viability, proliferation potential, phenotype, and differentiation potential of fresh ASCs and ASCs cryopreserved using different combinations of three cryoprotective agents: fetal bovine serum (FBS), dimethylsulfoxide (DMSO), and human platelet lysate (PL). The viability of the ASCs cryopreserved with 90% FBS and 10% DMSO, 95% FBS and 5% DMSO, and 97% PL and 3% DMSO was >80%, and the proliferation potentials, cell phenotypes, and differentiation potentials of these groups were similar to those of fresh ASCs. Together, our findings suggest that a combination of 97% PL and 3% DMSO is an ideal cryoprotective agent for the efficient cryopreservation of human ASCs. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of a second T-cell antigen receptor in human and mouse by an anti-peptide γ-chain-specific monoclonal antibody

International Nuclear Information System (INIS)

Ioannides, C.G.; Itoh, K.; Fox, F.E.; Pahwa, R.; Good, R.A.; Platsoucas, C.D.

1987-01-01

The authors developed a monoclonal antibody (mAb) (9D7) against a synthetic peptide (P13K) selected from the deduced amino acid sequence of the constant region of the λ chain of the murine T-cell antigen receptor (TCR) (amino acids 118-130). Using this mAb, they identified a putative second TCR expressed on peripheral blood lymphocytes from a patient with severe combined immunodeficiency (SCID) that were propagated in culture with recombinant interleukin 2 (rIL-2) and Con A. This mAb immunoprecipitated two polypeptide chains of 40 and 58 kDa under nonreducing conditions and of 40 and 56 kDa under reducing conditions from 125 I-labeled denatured lysates of T3 + WT31 - lymphocytes expanded in culture from a SCID patient. Chemical crosslinking of 125 I-labeled cells followed by immunoprecipitation with anti-Leu-4 mAb under nonreducing or reducing conditions revealed that the 40- and 56-kDa polypeptide chains were associated with the T3 differentiation antigen. These experiments were done with polyclonal cell populations. Cloned T3 + WT31 - cell populations are required to determine whether the TCR contains two λ polypeptide chains. Using the same 9D7 anti-P18K mAb and immunoblotting analysis, they identified a 35 kDa γ-chain polypeptide under reducing conditions expressed on purified L3T4 - Lyt2 - BALB/c mouse thymocytes. This γ-chain TCR is disulfide linked and has a molecular mass of 80 kDa under nonreducing conditions

Limited antigenic variation in the Trypanosoma cruzi candidate vaccine antigen TSA-1.

Science.gov (United States)

Knight, J M; Zingales, B; Bottazzi, M E; Hotez, P; Zhan, B

2014-12-01

Chagas disease (American trypanosomiasis caused by Trypanosoma cruzi) is one of the most important neglected tropical diseases in the Western Hemisphere. The toxicities and limited efficacies of current antitrypanosomal drugs have prompted a search for alternative technologies such as a therapeutic vaccine comprised of T. cruzi antigens, including a recombinant antigen encoding the N-terminal 65 kDa portion of Trypomastigote surface antigen-1 (TSA-1). With at least six known genetically distinct T. cruzi lineages, variability between the different lineages poses a unique challenge for the development of broadly effective therapeutic vaccine. The variability across the major lineages in the current vaccine candidate antigen TSA-1 has not previously been addressed. To assess the variation in TSA-1, we cloned and sequenced TSA-1 from several different T. cruzi strains representing three of the most clinically relevant lineages. Analysis of the different alleles showed limited variation in TSA-1 across the different strains and fit with the current theory for the evolution of the different lineages. Additionally, minimal variation in known antigenic epitopes for the HLA-A 02 allele suggests that interlineage variation in TSA-1 would not impair the range and efficacy of a vaccine containing TSA-1. © 2014 John Wiley & Sons Ltd.

BACTERIAL LYSATES FOR TOPICAL APPLICATION IN PREVENTION AND TREATMENT OF CHRONIC TONSILLITIS AMONG CHILDREN

Directory of Open Access Journals (Sweden)

T.I. Garashchenko

2006-01-01

Full Text Available The authors have carried on the research of the influence Imudon exerts (during topical application on the run of chronic tonsillitis among 48 children aged between 5 and 10 years old, being dispensary registrants. The sublingual application of a medicine 6 pills daily within 20 days demonstrated the frequency reduction of chronic tonsillitis acerbations by 2.9 times, as well as the reduction of total need in systemic antibacterial treatment by 10 times. Apart from that, the frequency of S. pyogenes group a exposure reduced by 3 times. The researchers noticed the tendency to normalization of pharynx biocenosis. Thus, Imudon may be recommended for the daily courses of treatment to the people, suffering from chronic tonsillitis, palatine tonsil auxesis and recurrent tonsillo-pharyngites.Key words: chronic tonsillitis, children, prevention, bacterial lysates.

Electrospun silk fibroin fibers for storage and controlled release of human platelet lysate.

Science.gov (United States)

Pignatelli, Cataldo; Perotto, Giovanni; Nardini, Marta; Cancedda, Ranieri; Mastrogiacomo, Maddalena; Athanassiou, Athanassia

2018-04-17

Human platelet lysate (hPL) is a pool of growth factors and cytokines able to induce regeneration of different tissues. Despite its good potentiality as therapeutic tool for regenerative medicine applications, hPL has been only moderately exploited in this field. A more widespread adoption has been limited because of its rapid degradation at room temperature that decreases its functionality. Another limiting factor for its extensive use is the difficulty of handling the hPL gels. In this work, silk fibroin-based patches were developed to address several points: improving the handling of hPL, enabling their delivery in a controlled manner and facilitating their storage by creating a device ready to use with expanded shelf life. Patches of fibroin loaded with hPL were synthesized by electrospinning to take advantage of the fibrous morphology. The release kinetics of the material was characterized and tuned through the control of fibroin crystallinity. Cell viability assays, performed with primary human dermal fibroblasts, demonstrated that fibroin is able to preserve the hPL biological activity and prolong its shelf-life. The strategy of storing and preserving small active molecules within a naturally-derived, protein-based fibrous scaffold was successfully implemented, leading to the design of a biocompatible device, which can potentially simplify the storage and the application of the hPL on a human patient, undergoing medical procedures such as surgery and wound care. Human platelets lysate (hPL) is a mixture of growth factors and cytokines able to induce the regeneration of damaged tissues. This study aims at enclosing hPL in a silk fibroin electrospun matrix to expand its utilization. Silk fibroin showed the ability to preserve the hPL activity at temperature up to 60 °C and the manipulation of fibroin's crystallinity provided a tool to modulate the hPL release kinetic. This entails the possibility to fabricate the hPL silk fibroin patches in advance and

Pathogen-free, plasma-poor platelet lysate and expansion of human mesenchymal stem cells.

Science.gov (United States)

Iudicone, Paola; Fioravanti, Daniela; Bonanno, Giuseppina; Miceli, Michelina; Lavorino, Claudio; Totta, Pierangela; Frati, Luigi; Nuti, Marianna; Pierelli, Luca

2014-01-27

Supplements to support clinical-grade cultures of mesenchymal stem cells (MSC) are required to promote growth and expansion of these cells. Platelet lysate (PL) is a human blood component which may replace animal serum in MSC cultures being rich in various growth factors. Here, we describe a plasma poor pathogen-free platelet lysate obtained by pooling 12 platelet (PLT) units, to produce a standardized and safe supplement for clinical-grade expansion of MSC. PL lots were obtained by combining 2 6-unit PLT pools in additive solution (AS) following a transfusional-based procedure including pathogen inactivation (PI) by Intercept technology and 3 cycles of freezing/thawing, followed by membrane removal. Three PI-PL and 3 control PL lots were produced to compare their ability to sustain bone marrow derived MSC selection and expansion. Moreover, two further PL, subjected to PI or not, were also produced starting from the same initial PLT pools to evaluate the impact of PI on growth factor concentration and capacity to sustain cell growth. Additional PI-PL lots were used for comparison with fetal bovine serum (FBS) on MSC expansion. Immunoregulatory properties of PI-PL-generated MSC were documented in vitro by mixed lymphocyte culture (MLC) and peripheral blood mononuclear cells (PBMC) mitogen induced proliferation. PI-PL and PL control lots had similar concentrations of 4 well-described growth factors endowed with MSC stimulating ability. Initial growth and MSC expansion by PI-PL and PL controls were comparable either using different MSC populations or in head to head experiments. Moreover, PI-PL and PL control sustained similar MSC growth of frozen/thawed MSC. Multilineage differentiation of PI-derived and PI-PL-derived MSC were maintained in any MSC cultures as well as their immunoregulatory properties. Finally, no direct impact of PI on growth factor concentration and MSC growth support was observed, whereas the capacity of FBS to sustain MSC expansion in basic

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...

Analyzing Protein Changes in Guinea Pig Tissue Lysates Using Non-guinea Pig Specific Antibodies: Procedures for Western Blotting and Examples Using 16 Individual Antibodies for Common CNS Proteins

National Research Council Canada - National Science Library

Johnson, Erik A; Daugherty, Kelly S

2006-01-01

... behavioral and protein changes due to the absence of guinea pig-specific antibodies. We have developed a procedure to determine the specificity of commercially available, non-guinea pig-specific antibodies in guinea pig lysates...

Comparison of antigen-specific T-cell responses of tuberculosis patients using complex or single antigens of Mycobacterium tuberculosis

DEFF Research Database (Denmark)

Mustafa, A S; Amoudy, H A; Wiker, H G

1998-01-01

GroES, rPstS, rGroEL and rDnaK) antigens of Mycobacterium tuberculosis. The responses of PBMC to these defined antigens were compared with the corresponding results obtained with complex antigens, such as whole-cell M. tuberculosis, M. tuberculosis culture filtrate (MT-CF) and cell wall antigens, as well...... as the vaccine strain, Mycobacterium bovis bacillus Calmette-Guerin (BCG). In addition, M. tuberculosis and MT-CF-induced T-cell lines were tested in the same assays against the panel of purified and complex antigens. The compiled data from PBMC and T-cell lines tested for antigen-induced proliferation and IFN...

E-NTPDase and E-ADA activities in lymphocytes associated with the immune response of rats experimentally infected with Toxoplasma gondii.

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Tonin, Alexandre A; Da Silva, Aleksandro S; Ruchel, Jader B; Rezer, João F P; Camillo, Giovana; Faccio, Luciana; França, Raqueli T; Leal, Daniela B R; Duarte, Marta M M F; Vogel, Fernada F; de la Rue, Mario L; Lopes, Sonia T A

2013-10-01

An investigation of E-NTPDase and E-ADA activities in lymphocytes from rats experimentally infected with Toxoplasma gondii was carried out in this study. For this purpose, twenty four adult male Wistar rats were divided in two groups/four subgroups (A1 and A2; B1 and B2-6 animal/each group), with "A" as uninfected and "B" inoculated with T. gondii (RH strain). Sampling was performed on days 5 and 10 post-infection (p.i.), with evaluation of hemogram, immunoglobulins (IgM and IgG) and activity of E-NTPDase and E-ADA in lymphocytes. Enzymes essays showed ATP hydrolysis increased on days 5 (PADA activity on lymphocytes was also increased in both evaluated periods (PADA increased activities observed on lymphocytes, it is possible to suggest their involvement in an anti-inflammatory response, consisting of a modulatory response, preventing excessive tissue damage caused by the infection with Toxoplasma gondii. Copyright © 2013 Elsevier Inc. All rights reserved.

Seroprevalence of Toxoplasma gondii and concurrent bartonella spp., feline immunodeficiency virus, and feline leukemia infections in cats from Grenada, West Indies

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Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline Immunodeficiency Virus (FIV), and Feline Leukemia Virus (FeLv) are related to Human Iimmunodeficiency Virus, and Human Leukemia Virus, respectively, and these viruses are immunosuppressive. In the present study, the prevale...

COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

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Rita G SOUSA

2014-03-01

Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

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

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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.

The effect of Toxoplasma gondii on animal behavior: playing cat and mouse.

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Webster, Joanne P

2007-05-01

A convincing body of evidence now exists to indicate that the ubiquitous protozoan Toxoplasma gondii can cause permanent behavioral changes in its host, even as a consequence of adult-acquired latent infection. Such behavioral alterations appear to be the product of strong selective pressures for the parasite to enhance transmission from its intermediate host reservoir, primarily rodent, to its feline definitive host, wherein sexual reproduction can occur and the life cycle completed. This article reviews evidence of behavioral alterations in animal hosts and considers what these may elucidate about the potential mechanisms involved and what implications such alterations could have on animal and human health.

Outbreak of caprine abortion by Toxoplasma gondii in Midwest Brazil

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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.

Detection of Toxoplasma gondii in a free-ranging giant anteater

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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.

Myenteric neuronal plasticity induced by Toxoplasma gondii (genotype III on the duodenum of rats

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Rodrigo M. Papazian-Cabanas

2012-09-01

Full Text Available The effects of acute and chronic infection caused by Toxoplasma gondii on duodenal myenteric neurons were analyzed. Eighteen rats were assigned into four groups: Acute Control Group (ACG, n=4; Acute Experimental Group (AEG, n=4; Chronic Control Group (CCG, n=5; and Chronic Experimental Group (CEG, n=5. Rats from the AEG and CEG were inoculated orally with 105 genotype III (BTU-II strain tachyzoites of T. gondii isolated from a dog with neurological signs. Acute groups were killed after 24 hours after the inoculation and the chronic groups after 30 days. Whole-mount from the duodenum were stained with Giemsa. The population density of myenteric neurons, as well the body cell, nuclear and cytoplasmic area were analyzed. Both acute and chronic toxoplasmic infection did not provoke neuronal loss. On the other hand, plastic alterations were observed: decreasing of the nuclear and cytoplasmic area during the acute phase and neuronal hypertrophy during the chronic phase.Foram analisados os efeitos da infecção aguda e crônica provocada pelo Toxoplasma gondii sobre os neurônios mientéricos do duodeno. Dezoito ratos foram divididos em quatro grupos: Grupo Controle Agudo (GCA, n= 4, Grupo Experimental Agudo (GEA, n=4, Grupo Controle Crônico (GCC, n=5 e Grupo Experimental Crônico (GEC, n=5. Os animais do GEA e GEC receberam por via oral 10 5 taquizoítos de Toxoplasma gondii da cepa BTUII (genótipo III isolada de um cão com sintomatologia neurológica. Os grupos agudos foram submetidos à eutanásia após 24 horas e os crônicos após 30 dias da inoculação. Preparados totais do duodeno foram corados com Giemsa. A densidade populacional dos neurônios mientéricos, bem como a área do corpo celular, núcleo e citoplasma foram analisados. Ambas, as infecções toxoplásmicas aguda e crônica não provocaram a perda neuronal. Por outro lado, alterações plásticas foram observadas: diminuição da área nuclear e citoplasmática durante a fase

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

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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.

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

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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...

Lysine acetyltransferase GCN5b interacts with AP2 factors and is required for Toxoplasma gondii proliferation.

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Jiachen Wang

2014-01-01

Full Text Available Histone acetylation has been linked to developmental changes in gene expression and is a validated drug target of apicomplexan parasites, but little is known about the roles of individual histone modifying enzymes and how they are recruited to target genes. The protozoan parasite Toxoplasma gondii (phylum Apicomplexa is unusual among invertebrates in possessing two GCN5-family lysine acetyltransferases (KATs. While GCN5a is required for gene expression in response to alkaline stress, this KAT is dispensable for parasite proliferation in normal culture conditions. In contrast, GCN5b cannot be disrupted, suggesting it is essential for Toxoplasma viability. To further explore the function of GCN5b, we generated clonal parasites expressing an inducible HA-tagged dominant-negative form of GCN5b containing a point mutation that ablates enzymatic activity (E703G. Stabilization of this dominant-negative GCN5b was mediated through ligand-binding to a destabilization domain (dd fused to the protein. Induced accumulation of the ddHAGCN5b(E703G protein led to a rapid arrest in parasite replication. Growth arrest was accompanied by a decrease in histone H3 acetylation at specific lysine residues as well as reduced expression of GCN5b target genes in GCN5b(E703G parasites, which were identified using chromatin immunoprecipitation coupled with microarray hybridization (ChIP-chip. Proteomics studies revealed that GCN5b interacts with AP2-domain proteins, apicomplexan plant-like transcription factors, as well as a "core complex" that includes the co-activator ADA2-A, TFIID subunits, LEO1 polymerase-associated factor (Paf1 subunit, and RRM proteins. The dominant-negative phenotype of ddHAGCN5b(E703G parasites, considered with the proteomics and ChIP-chip data, indicate that GCN5b plays a central role in transcriptional and chromatin remodeling complexes. We conclude that GCN5b has a non-redundant and indispensable role in regulating gene expression required

The prevalence of toxoplasma igG and IgM in pregnant women residing in Rawalpindi

International Nuclear Information System (INIS)

Kausar, N.; Akhtar, S.; Ikram, A.

2010-01-01

Objective: To determine the prevalence of Toxoplasma gondii antibodies (IgG/IgM) among pregnant women visiting Military Hospital Rawalpindi and to develop a relationship between various risk factors and disease prevalence. Methods: One thousand pregnant women reporting in out patient Gynaecology department of Military Hospital (MH) Rawalpindi from October 2008 through January 2009 for antenatal check up were included in the study. Their serum samples were tested for the presence of Toxoplasma IgM and IgG immunoglobulins. Enzyme Linked immunosorbent assay test kits for both IgG and IgM were used to detect 1: gondii immunoglobulins in serum samples. Rest of the serum was stored at -20 degree C. Results: Of the 1000 women sampled at hospital, 46 (4.6%) had evidence of past infection and were seropositive for immunoglobulins of T. gondii IgG, while none of them were seropositive for IgM immunoglobulin, suggesting absence of recent infections during pregnancy. Conclusion: In twin cities of Islamabad and Rawalpindi, the sero prevalence of T. gondii IgG in pregnant women is relatively high (4.6%) as compared to other areas nearby. Consequently, the risk of, primary infection during pregnancy and the potential for congenital infection of foetus remains there as a large number of pregnant women were sero-negative for both the antibodies.

Characterization of Antigen-Specific B Cells Using Nominal Antigen-Coated Flow-Beads

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Akl, Ahmed; Lepetit, Maud; Crochette, Romain; Giral, Magali; Lepourry, Julie; Pallier, Annaick; Castagnet, Stéphanie; Dugast, Emilie; Guillot-Gueguen, Cécile; Jacq-Foucher, Marylène; Saulquin, Xavier; Cesbron, Anne; Laplaud, David; Nicot, Arnaud; Brouard, Sophie; Soulillou, Jean-Paul

2013-01-01

In order to characterize the reactivity of B cells against nominal antigens, a method based on the coupling of antigens onto the surface of fluorescent core polystyrene beads was developed. We first demonstrate that murine B cells with a human MOG-specific BCR are able to interact with MOG-coated beads and do not recognize beads coated with human albumin or pp65. B cells purified from human healthy volunteer blood or immunized individuals were tested for their ability to interact with various nominal antigens, including viral, vaccine, self and alloantigens, chosen for their usefulness in studying a variety of pathological processes. A substantial amount of B cells binding self-antigen MOG-coated beads can be detected in normal blood. Furthermore, greater frequencies of B cell against anti-Tetanic Toxin or anti-EBNA1 were observed in primed individuals. This method can reveal increased frequencies of anti-HLA committed B cells in patients with circulating anti-HLA antibodies compared to unsensitized patients and normal individuals. Of interest, those specific CD19 cells were preferentially identified within CD27−IgD+ (i-e naïve) subset. These observations suggest that a broad range of medical situations could benefit from a tool that allows the detection, the quantification and the characterization of antigen-specific blood B cells. PMID:24386360

Forward genetic screening identifies a small molecule that blocks Toxoplasma gondii growth by inhibiting both host- and parasite-encoded kinases.

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Kevin M Brown

2014-06-01

Full Text Available The simultaneous targeting of host and pathogen processes represents an untapped approach for the treatment of intracellular infections. Hypoxia-inducible factor-1 (HIF-1 is a host cell transcription factor that is activated by and required for the growth of the intracellular protozoan parasite Toxoplasma gondii at physiological oxygen levels. Parasite activation of HIF-1 is blocked by inhibiting the family of closely related Activin-Like Kinase (ALK host cell receptors ALK4, ALK5, and ALK7, which was determined in part by use of an ALK4,5,7 inhibitor named SB505124. Besides inhibiting HIF-1 activation, SB505124 also potently blocks parasite replication under normoxic conditions. To determine whether SB505124 inhibition of parasite growth was exclusively due to inhibition of ALK4,5,7 or because the drug inhibited a second kinase, SB505124-resistant parasites were isolated by chemical mutagenesis. Whole-genome sequencing of these mutants revealed mutations in the Toxoplasma MAP kinase, TgMAPK1. Allelic replacement of mutant TgMAPK1 alleles into wild-type parasites was sufficient to confer SB505124 resistance. SB505124 independently impacts TgMAPK1 and ALK4,5,7 signaling since drug resistant parasites could not activate HIF-1 in the presence of SB505124 or grow in HIF-1 deficient cells. In addition, TgMAPK1 kinase activity is inhibited by SB505124. Finally, mice treated with SB505124 had significantly lower tissue burdens following Toxoplasma infection. These data therefore identify SB505124 as a novel small molecule inhibitor that acts by inhibiting two distinct targets, host HIF-1 and TgMAPK1.

Progress of dendritic cell-based cancer vaccines for patients with hematological malignancies.

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Ni, Ming; Hoffmann, Jean-Marc; Schmitt, Michael; Schmitt, Anita

2016-09-01

Dendritic cells (DCs) are the most professional antigen-presenting cells eliciting cellular and humoral immune responses against cancer cells by expressing these antigens on MHC class I/II complexes to T cells. Therefore, they have been employed in many clinical trials as cancer vaccines for patients with cancer. This review focuses on the use of DCs in leukemia patients expressing leukemia-associated antigens (LAAs). The contribution of both stimulating vs. tolerogenic DCs as well as of other factors to the milieu of anti-leukemia immune responses are discussed. Several DC vaccination strategies like leukemia lysate, proteins and peptides have been developed. Next generation DC vaccines comprise transduction of DCs with retroviral vectors encoding for LAAs, cytokines and costimulatory molecules as well as transfection of DCs with naked RNA encoding for LAAs. Published as well as ongoing clinical trials are reported and critically reviewed. Future results will demonstrate whether next-generation DCs are really superior to conventional pulsing with peptide, protein or tumor lysate. However, currently available methods based on nucleic acid transfection/transduction are tempting in terms of material production costs and time for clinical application according to good manufacturing practice (GMP).

Radioimmunoassay of measles virus hemagglutinin protein G

International Nuclear Information System (INIS)

Lund, G.A.; Salmi, A.A.

1982-01-01

Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 μg of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells. (Auth.)

Radioimmunoassay of measles virus hemagglutinin protein G

Energy Technology Data Exchange (ETDEWEB)

Lund, G A; Salmi, A A [Turku Univ. (Finland)

1982-08-01

Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 ..mu..g of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells.

Suppression of immune surveillance in melanoma [Immunotherapy of metastatic melanoma by reversal of immune suppression

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Biggs, M. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eiselein, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2001-06-01

In this paper we develop the hypothesis that a significant fraction of patients with advanced melanoma can be successfully treated with immunotherapy. Reversal of antigen-specific immune suppression to melanoma polypeptide antigens is an essential, first step. We postulate the key regulation of CTL responses resides within the CD4+ T-lymphocytes and macrophage/dendritic cells. There is a pluri-potential cell within this regulatory arm that functions either as a Th1 cell or as a suppressor T-cell, Ths, depending on how antigen is presented. We have shown that poliovirus 1 Sabin will lyse human melanoma cells in tissue culture, and a special "vaccine" prepared from this lysis actively stimulates Ths cell function. The Ths arm of the regulatory system can be down-regulated with cyclophosphamide given 24 hours after the vaccine. The capacity to generate a CTL response is retained. The summary conclusion is that a phase 1 clinical trial in advanced melanoma using the special viral-tumor-lysate followed by cyclophosphamide, plus expanded autologous dendritic cells sensitized with the polypeptide epitopes captained in the viral-lysate will produce beneficial results.

Comparison of clinical grade human platelet lysates for cultivation of mesenchymal stromal cells from bone marrow and adipose tissue

DEFF Research Database (Denmark)

Juhl, Morten; Tratwal, Josefine; Follin, Bjarke

2016-01-01

be devoid of any animal derived components. We have evaluated whether human Platelet Lysate (hPL) could be an attractive alternative to animal supplements. METHODS: MSCs from bone marrow (BMSCs) and adipose tissue-derived stromal cells (ASCs) obtained from three donors were culture expanded in three...... culture conditions with 10% fetal bovine serum (FBS). Cell morphology, proliferation, phenotype, genomic stability, and differentiation potential were analyzed. RESULTS: Regardless of manufacturer, BMSCs and ASCs cultured in hPL media showed a significant increase in proliferation capacity compared to FBS...

Serum-converted platelet lysate can substitute for fetal bovine serum in human mesenchymal stromal cell cultures.

Science.gov (United States)

Mojica-Henshaw, Mariluz P; Jacobson, Pam; Morris, Julie; Kelley, Linda; Pierce, Jan; Boyer, Michael; Reems, Jo-Anna

2013-12-01

Fetal bovine serum (FBS) is commonly used as a serum supplement for culturing human mesenchymal stromal cells (hMSCs). However, human cells grown in FBS, especially for extended periods, risk potential exposure to bovine immunogenic proteins and infectious agents. To address this issue, we investigated the ability of a novel human platelet serum supplement to substitute for FBS in hMSC cultures. Platelet lysate-serum (PL-serum) was converted from platelet lysate-plasma (PL-plasma) that was manufactured from pooled platelet-rich plasma (PRP) apheresis units. Growth factor levels and the number of residual intact platelets in PL-serum and PL-plasma were compared with enzyme-linked immunosorbent assays and flow cytometry, respectively. Proliferation responses of hMSCs cultured in PL-serum, PL-plasma, or FBS were assessed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the immunophenotype of harvested hMSCs was evaluated by flow cytometry and tri-lineage differentiation potential was evaluated by assessing adipogenic, osteogenic and chondrogenic development. Selected growth factor levels in PL-serum were not significantly different from PL-plasma (P > 0.05). hMSC cultures supplemented with PL-serum had comparable growth kinetics to PL-plasma, and hMSC yields were consistently greater than with FBS. hMSCs harvested from cultures supplemented with PL-serum, PL-plasma or FBS had similar cell surface phenotypes and maintained tri-lineage differentiation potential. PL-serum, similar to PL-plasma, can substitute for FBS in hMSC cultures. Use of PL-serum, in contrast to PL-plasma, has an added advantage of not requiring addition of a xenogeneic source of heparin, providing a completely xeno-free culture medium. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Facts on the fragmentation of antigens in presenting cells, on the association of antigen fragments with MHC molecules in cell-free systems, and speculation on the cell biology of antigen processing

DEFF Research Database (Denmark)

Werdelin, O; Mouritsen, S; Petersen, B L

1988-01-01

The processing of a protein antigen is a multi-step event taking place in antigen-presenting cells. Processing is a prerequisite for the recognition of most antigens by T lymphocytes. The antigen is ingested by endocytosis, transported to an acid cellular compartment and subjected to proteolytic...... fragmentation. Some of the antigen fragments bind to MHC class II molecules and are transported to the surface of the antigen-presenting cell where the actual presentation to T lymphocytes occurs. The nature of the processed antigen, how and where it is derived and subsequently becomes associated with MHC...... molecules are the questions discussed in this review. To us, the entire concept of processing has appeal not only because it explains some hitherto well-established, but poorly understood, phenomena such as the fact that T lymphocytes focus their attention entirely upon antigens on other cells. It has...

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

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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.

Prevalence of toxoplasma antibodies according to age with comments on the risk of prenatal infection.

OpenAIRE

van der Veen, J.; Polak, M. F.

1980-01-01

Sera from 1661 persons in 12 age groups from 0 to 79 years were titrated for toxoplasma antibodies in the indirect immunofluorescence test. The sera were collected from patients with symptoms suggestive of acute, mainly respiratory, viral infections. After the first year of life, the prevalence of antibodies started to rise, reaching 59% between 40 and 79 years of age. From the prevalence of antibodies in different age groups the annual infection risk, i.e, the risk of a non-immune person acq...

Natural selection promotes antigenic evolvability.

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Graves, Christopher J; Ros, Vera I D; Stevenson, Brian; Sniegowski, Paul D; Brisson, Dustin

2013-01-01

The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed 'cassettes' that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios) and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish chronic infections.

Natural selection promotes antigenic evolvability.

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Christopher J Graves

Full Text Available The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed 'cassettes' that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish

Concepts and applications for influenza antigenic cartography

Science.gov (United States)

Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

2011-01-01

Influenza antigenic cartography projects influenza antigens into a two or three dimensional map based on immunological datasets, such as hemagglutination inhibition and microneutralization assays. A robust antigenic cartography can facilitate influenza vaccine strain selection since the antigenic map can simplify data interpretation through intuitive antigenic map. However, antigenic cartography construction is not trivial due to the challenging features embedded in the immunological data, such as data incompleteness, high noises, and low reactors. To overcome these challenges, we developed a computational method, temporal Matrix Completion-Multidimensional Scaling (MC-MDS), by adapting the low rank MC concept from the movie recommendation system in Netflix and the MDS method from geographic cartography construction. The application on H3N2 and 2009 pandemic H1N1 influenza A viruses demonstrates that temporal MC-MDS is effective and efficient in constructing influenza antigenic cartography. The web sever is available at http://sysbio.cvm.msstate.edu/AntigenMap. PMID:21761589