37 research outputs found

    Identification of Class I HLA T Cell Control Epitopes for West Nile Virus

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    The recent West Nile virus (WNV) outbreak in the United States underscores the importance of understanding human immune responses to this pathogen. Via the presentation of viral peptide ligands at the cell surface, class I HLA mediate the T cell recognition and killing of WNV infected cells. At this time, there are two key unknowns in regards to understanding protective T cell immunity: 1) the number of viral ligands presented by the HLA of infected cells, and 2) the distribution of T cell responses to these available HLA/viral complexes. Here, comparative mass spectroscopy was applied to determine the number of WNV peptides presented by the HLA-A*11:01 of infected cells after which T cell responses to these HLA/WNV complexes were assessed. Six viral peptides derived from capsid, NS3, NS4b, and NS5 were presented. When T cells from infected individuals were tested for reactivity to these six viral ligands, polyfunctional T cells were focused on the GTL9 WNV capsid peptide, ligands from NS3, NS4b, and NS5 were less immunogenic, and two ligands were largely inert, demonstrating that class I HLA reduce the WNV polyprotein to a handful of immune targets and that polyfunctional T cells recognize infections by zeroing in on particular HLA/WNV epitopes. Such dominant HLA/peptide epitopes are poised to drive the development of WNV vaccines that elicit protective T cells as well as providing key antigens for immunoassays that establish correlates of viral immunity. © 2013 Kaabinejadian et al

    Growth delay of human bladder cancer cells by Prostate Stem Cell Antigen downregulation is associated with activation of immune signaling pathways

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    <p>Abstract</p> <p>Background</p> <p>Prostate stem cell antigen (PSCA) is a glycosylphosphatidylinositol (GPI) anchored protein expressed not only in prostate but also in pancreas and bladder cancer as shown by immunohistochemistry and mRNA analysis. It has been targeted by monoclonal antibodies in preclinical animal models and more recently in a clinical trial in prostate cancer patients. The biological role played in tumor growth is presently unknown. In this report we have characterized the contribution of PSCA expression to tumor growth.</p> <p>Methods</p> <p>A bladder cell line was engineered to express a doxycycline (dox) regulated shRNA against PSCA. To shed light on the PSCA biological role in tumor growth, microarray analysis was carried out as a function of PSCA expression. Expression of gene set of interest was further analyzed by qPCR</p> <p>Results</p> <p>Down regulation of the PSCA expression was associated with reduced cell proliferation <it>in vitro </it>and <it>in vivo</it>. Mice bearing subcutaneous tumors showed a reduced tumor growth upon treatment with dox, which effectively induced shRNA against PSCA as revealed by GFP expression. Pathway analysis of deregulated genes suggests a statistical significant association between PSCA downregulation and activation of genes downstream of the IFNα/ÎČ receptor.</p> <p>Conclusions</p> <p>These experiments established for the first time a correlation between the level of PSCA expression and tumor growth and suggest a role of PSCA in counteracting the natural immune response.</p

    Public attitudes toward biodiversity-friendly greenspace management in Europe

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    Increasing urbanization worldwide calls for more sustainable urban development. Simultaneously, the global biodiversity crisis accentuates the need of fostering biodiversity within cities. Policies supporting urban nature conservation need to understand people's acceptance of biodiversity-friendly greenspace management. We surveyed more than 2,000 people in 19 European cities about their attitudes toward near-natural urban grassland management in public greenspaces, and related their responses to nine sociocultural parameters. Results reveal that people across Europe can support urban biodiversity, yet within the frames of a generally tidy appearance of public greenery. Younger people and those using greenspaces for a greater variety of activities were more likely to favor biodiversity-friendly greenspace management. Additionally, people who were aware of the meaning of biodiversity and those stating responsibility for biodiversity conservation particularly supported biodiversity-friendly greenspace management. Our results point at explicit measures like environmental education to increase public acceptance of policies that facilitate nature conservation within cities

    Quantitative genetics of immunity and life history under different photoperiods

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    Insects with complex life-cycles should optimize age and size at maturity during larval development. When inhabiting seasonal environments, organisms have limited reproductive periods and face fundamental decisions: individuals that reach maturity late in season have to either reproduce at a small size or increase their growth rates. Increasing growth rates is costly in insects because of higher juvenile mortality, decreased adult survival or increased susceptibility to parasitism by bacteria and viruses via compromised immune function. Environmental changes such as seasonality can also alter the quantitative genetic architecture. Here, we explore the quantitative genetics of life history and immunity traits under two experimentally induced seasonal environments in the cricket Gryllus bimaculatus. Seasonality affected the life history but not the immune phenotypes. Individuals under decreasing day length developed slower and grew to a bigger size. We found ample additive genetic variance and heritability for components of immunity (haemocyte densities, proPhenoloxidase activity, resistance against Serratia marcescens), and for the life history traits, age and size at maturity. Despite genetic covariance among traits, the structure of G was inconsistent with genetically based trade-off between life history and immune traits (for example, a strong positive genetic correlation between growth rate and haemocyte density was estimated). However, conditional evolvabilities support the idea that genetic covariance structure limits the capacity of individual traits to evolve independently. We found no evidence for G × E interactions arising from the experimentally induced seasonality

    Identification and Functional Analysis of Light-Responsive Unique Genes and Gene Family Members in Rice

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    Functional redundancy limits detailed analysis of genes in many organisms. Here, we report a method to efficiently overcome this obstacle by combining gene expression data with analysis of gene-indexed mutants. Using a rice NSF45K oligo-microarray to compare 2-week-old light- and dark-grown rice leaf tissue, we identified 365 genes that showed significant 8-fold or greater induction in the light relative to dark conditions. We then screened collections of rice T-DNA insertional mutants to identify rice lines with mutations in the strongly light-induced genes. From this analysis, we identified 74 different lines comprising two independent mutant lines for each of 37 light-induced genes. This list was further refined by mining gene expression data to exclude genes that had potential functional redundancy due to co-expressed family members (12 genes) and genes that had inconsistent light responses across other publicly available microarray datasets (five genes). We next characterized the phenotypes of rice lines carrying mutations in ten of the remaining candidate genes and then carried out co-expression analysis associated with these genes. This analysis effectively provided candidate functions for two genes of previously unknown function and for one gene not directly linked to the tested biochemical pathways. These data demonstrate the efficiency of combining gene family-based expression profiles with analyses of insertional mutants to identify novel genes and their functions, even among members of multi-gene families

    Global urban environmental change drives adaptation in white clover.

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    A minƑsĂ©gi idƑtöltĂ©s hatĂĄsa a gyermek nyelvi fejlƑdĂ©sĂ©re

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    A szakdolgozat tĂ©mĂĄja a szĂŒlƑ gyermekĂ©vel egyĂŒtt töltött idejĂ©nek hatĂĄsa a gyermek nyelvi fejlƑdĂ©sĂ©re. Mely idƑtöltĂ©si mĂłdok hogyan hatnak a fejlƑdĂ©si szakasz alapjaira, a beszĂ©d indulĂĄsĂĄra. A kisgyermek normĂĄl ĂŒtemƱ Ă©s atipikus beszĂ©dfejlƑdĂ©sĂ©t bemutatva Ă©s ezen fejlƑdĂ©st befolyĂĄsolĂł tĂ©nyezƑket szĂĄmba vĂ©ve, valamint a befolyĂĄsolĂł tĂ©nyezƑk közĂŒl kiragadva az anya-gyermek kapcsolatot Ă©s annak hatĂĄsĂĄt, kerĂŒlt felĂ©pĂ­tĂ©sre az elmĂ©leti hĂĄttĂ©r.szakirĂĄnyĂș tovĂĄbbkĂ©pzĂ©sNyelv- Ă©s beszĂ©dfejlesztƑ terĂŒleten pedagĂłgus szakvizsgĂĄra felkĂ©szĂ­tƑ szakirĂĄnyĂș tovĂĄbbkĂ©pzĂ©si sza

    Effect of nitaxozanide and pyrimethamine on astrocytes infected by Toxoplasma gondii in vitro.

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    BACKGROUND AND AIMS: T. gondii is a causal agent of encephalitis in immunocompromised patients. Pyrimethamine (PYR) has been the treatment of choice for toxoplasmosis. The aim of this study was to analyze the effect of nitazoxanide and pyrimethamine on astrocytes infected with T. gondii in vitro. METHODS: Rat astrocytes were cultured and infected with T. gondii. The effect of nitazoxanide (10, 20 and 30 mug/mL) and pyrimethamine (7, 10 and 13 mug/mL) on astrocytes infected was evaluated at 24 and 48 h post-infection. Tachyzoites and astrocytes were detected by the immunocytochemical method. T. gondii viability in astrocytes infected and treated with NTZ and PYR as well as NTZ and PYR cytotoxicity on astrocytes in vitro were evaluated by the MTT assay. RESULTS: The number of parasites in astrocytes treated with the drugs was significantly reduced when compared to control (p <0.001) at 24 and 48 h. Nitazoxanide produced 97% T. gondii death in a concentration of 10 mug/mL in 48 h infected astrocytes. At 48 h, the death rate of T. gondii was higher when treated with nitazoxanide than with pyrimethamine. A higher toxicity rate in astrocyte was observed when using pyrimethamine at 40 mug/mL. CONCLUSIONS: Nitazoxanide reduced T. gondii infection more efficiently than pyrimethamine and is not cytotoxic to astrocytes at the administered dose.Copyright ?ïżœ 2013 IMSS. Published by Elsevier Inc. All rights reserved
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