37 research outputs found

    Effects of 15-Deoxy-Δ12,14-Prostaglandin J2 (15d-PGJ2) and Rosiglitazone on Human Vδ2+ T Cells

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    BACKGROUND:Thiazolidinediones (TZD) class of drugs, and 15-deoxy-D12,14-prostaglandin J2 (15d-PGJ2) are immune regulators predicted to modulate human autoimmune disease. Their effects on gammadelta T cells, which are involved in animal model and human and animal autoimmune diseases, are unknown. METHODOLOGY/PRINCIPAL FINDINGS:We characterized the activity of rosiglitazone (from the TZD class of drugs) and 15d-PGJ2 in human Vdelta2 T cells. We found that 15d-PGJ2 and rosiglitazone had different effects on Vdelta2 T cell functions. Both 15d-PGJ2 and rosiglitazone suppressed Vdelta2 T cell proliferation in response to IPP and IL2. However, only 15d-PGJ2 suppressed functional responses including cytokine production, degranulation and cytotoxicity against tumor cells. The mechanism for 15d-PGJ2 effects on Vdelta2 T cells acts through inhibiting Erk activation. In contrast, rosiglitazone did not affect Erk activation but the IL2 signaling pathway, which accounts for rosiglitazone suppression of IL2-dependent, Vdelta2 T cell proliferation without affecting TCR-dependent functions. Rosiglitazone and 15d-PGJ2 are designed to be peroxisome proliferator-activated receptor gamma (PPARgamma) ligands and PPARgamma was expressed in Vdelta2 T cell. Surprisingly, when PPARgamma levels were lowered by specific siRNA, 15d-PGJ2 and rosiglitazone were still active, suggesting their target of action induces cellular proteins other than PPARgamma. CONCLUSIONS/SIGNIFICANCE:The current findings expand our understanding of how the immune system is regulated by rosiglitazone and 15d-PGJ2 and will be important to evaluate these compounds as therapeutic agents in human autoimmune disease

    Man and the Last Great Wilderness: Human Impact on the Deep Sea

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    The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life – SYNDEEP workshop (September 2008). A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past) to exploitation (present). We predict that from now and into the future, increases in atmospheric CO2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this review with a short discussion on protection and management methods

    Developmental pathway for potent V1V2-directed HIV-neutralizing antibodies.

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    CAPRISA, 2014.Antibodies capable of neutralizing HIV-1 often target variable regions 1 and 2 (V1V2) of the HIV-1 envelope, but the mechanism of their elicitation has been unclear. Here we define the developmental pathway by which such antibodies are generated and acquire the requisite molecular characteristics for neutralization. Twelve somatically related neutralizing antibodies (CAP256-VRC26.01-12) were isolated from donor CAP256 (from the Centre for the AIDS Programme of Research in South Africa (CAPRISA)); each antibody contained the protruding tyrosine-sulphated, anionic antigen-binding loop (complementarity-determining region (CDR) H3) characteristic of this category of antibodies. Their unmutated ancestor emerged between weeks 30-38 post-infection with a 35-residue CDR H3, and neutralized the virus that superinfected this individual 15 weeks after initial infection. Improved neutralization breadth and potency occurred by week 59 with modest affinity maturation, and was preceded by extensive diversification of the virus population. HIV-1 V1V2-directed neutralizing antibodies can thus develop relatively rapidly through initial selection of B cells with a long CDR H3, and limited subsequent somatic hypermutation. These data provide important insights relevant to HIV-1 vaccine development

    The analysis and quantification of a clonal B cell response in a hyperimmunized anti-D donor

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    Healthy volunteers are hyperimmunized with RhD-positive red cells in order to obtain plasma containing high titres of anti-D immunoglobulin, which is used for the prevention of haemolytic disease of the fetus and newborn. We analysed the anti-D immune response in a donor who had been hyperimmunized for 7 years and who showed declining anti-D titres despite re-immunization. A phage display library representing the complete immunorepertoire and a second library representing the IGHV3 superspecies family genes (IGHV3s) repertoire in the donor were constructed and analysed. A clonal Ig-gene rearrangement was quantified in the peripheral blood by limiting dilution polymerase chain reaction (PCR) All RhD-binding phages from both libraries, except one, had heavy chains with IGH–VDJ rearrangements of the same clonal origin, but with different patterns of somatic mutations and joined with different light chains. Limiting dilution PCR performed on mRNA and genomic DNA showed a frequency of 1 clonal B cell in 2000 IgG1/3-positive B cells. We show the presence of clonally related RhD-specific B cells in a hyperimmunized anti-D donor who had declining anti-D titres and who was unresponsive to re-immunization. Furthermore, we found a high frequency of clonal B cells. These results contribute to the understanding of the immune response against RhD in hyperimmunized anti-D donors

    Evaluation of linguistic and prosodic features for detection of Alzheimer’s disease in Turkish conversational speech

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    Due to copyright restrictions, the access to the full text of this article is only available via subscription.Automatic diagnosis and monitoring of Alzheimer’s disease can have a significant impact on society as well as the well-being of patients. The part of the brain cortex that processes language abilities is one of the earliest parts to be affected by the disease. Therefore, detection of Alzheimer’s disease using speech-based features is gaining increasing attention. Here, we investigated an extensive set of features based on speech prosody as well as linguistic features derived from transcriptions of Turkish conversations with subjects with and without Alzheimer’s disease. Unlike most standardized tests that focus on memory recall or structured conversations, spontaneous unstructured conversations are conducted with the subjects in informal settings. Age-, education-, and gender-controlled experiments are performed to eliminate the effects of those three variables. Experimental results show that the proposed features extracted from the speech signal can be used to discriminate between the control group and the patients with Alzheimer’s disease. Prosodic features performed significantly better than the linguistic features. Classification accuracy over 80% was obtained with three of the prosodic features, but experiments with feature fusion did not further improve the classification performance
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