136 research outputs found

    ĐŸŃ€ĐŸĐ±Đ»Đ”ĐŒŃ‹ уĐČĐ”Đ»ĐžŃ‡Đ”ĐœĐžŃ ĐżŃ€ĐŸĐŽŃƒĐșтоĐČĐœĐŸŃŃ‚Đž АПК ĐČ ĐŁĐșŃ€Đ°ĐžĐœĐ” Đž путо ĐżĐŸĐČŃ‹ŃˆĐ”ĐœĐžŃ Đ”ĐłĐŸ ĐżĐŸŃ‚Đ”ĐœŃ†ĐžĐ°Đ»Đ°

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    ĐŠĐ”Đ»ŃŒŃŽ статьо яĐČĐ»ŃĐ”Ń‚ŃŃ ĐžĐ·ŃƒŃ‡Đ”ĐœĐžĐ” ĐżŃ€ĐžŃ‡ĐžĐœ ŃĐœĐžĐ¶Đ”ĐœĐžŃ ĐżĐŸĐșазатДлДĐč ĐżŃ€ĐŸĐŽŃƒĐșтоĐČĐœĐŸŃŃ‚Đž ĐČ Đ°ĐłŃ€ĐŸĐżŃ€ĐŸĐŒŃ‹ŃˆĐ»Đ”ĐœĐœĐŸĐŒ ĐșĐŸĐŒĐżĐ»Đ”ĐșсД Đž ĐżŃƒŃ‚Đ”Đč ĐżĐŸĐČŃ‹ŃˆĐ”ĐœĐžŃ ĐżŃ€ĐŸĐŽŃƒĐșтоĐČĐœĐŸŃŃ‚Đž ŃĐ”Đ»ŃŒŃĐșĐŸŃ…ĐŸĐ·ŃĐčстĐČĐ”ĐœĐœŃ‹Ń… ĐșŃƒĐ»ŃŒŃ‚ŃƒŃ€

    Mouse antibody of IgM class is prone to non-enzymatic cleavage between CH1 and CH2 domains

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    Abstract IgM is a multivalent antibody which evolved as a first line defense of adaptive immunity. It consists of heavy and light chains assembled into a complex oligomer. In mouse serum there are two forms of IgM, a full-length and a truncated one. The latter contains Ό’ chain, which lacks a variable region. Although Ό’ chain was discovered many years ago, its origin has not yet been elucidated. Our results indicate that Ό’ chain is generated from a full-length heavy chain by non-enzymatic cleavage of the protein backbone. The cleavage occurred specifically after Asn209 and is prevented by mutating this residue into any other amino acid. The process requires the presence of other proteins, preferentially with an acidic isoelectric point, and is facilitated by neutral or alkaline pH. This unique characteristic of the investigated phenomenon distinguishes it from other, already described, Asn-dependent protein reactions. A single IgM molecule is able to bind up to 12 epitopes via its antigen binding fragments (Fabs). The cleavage at Asn209 generates truncated IgM molecules and free Fabs, resulting in a reduced IgM valence and probably affecting IgM functionality in vivo

    Intracranial injection of dengue virus induces interferon stimulated genes and CD8(+) T cell infiltration by sphingosine kinase 1 independent pathways

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    We have previously reported that the absence of sphingosine kinase 1 (SK1) affects both dengue virus (DENV) infection and innate immune responses in vitro. Here we aimed to define SK1-dependancy of DENV-induced disease and the associated innate responses in vivo. The lack of a reliable mouse model with a fully competent interferon response for DENV infection is a challenge, and here we use an experimental model of DENV infection in the brain of immunocompetent mice. Intracranial injection of DENV-2 into C57BL/6 mice induced body weight loss and neurological symptoms which was associated with a high level of DENV RNA in the brain. Body weight loss and DENV RNA level tended to be greater in SK1-/- compared with wildtype (WT) mice. Brain infection with DENV-2 is associated with the induction of interferon-ÎČ (IFN-ÎČ) and IFN-stimulated gene (ISG) expression including viperin, Ifi27l2a, IRF7, and CXCL10 without any significant differences between WT and SK1-/- mice. The SK2 and sphingosine-1-phosphate (S1P) levels in the brain were unchanged by DENV infection or the lack of SK1. Histological analysis demonstrated the presence of a cellular infiltrate in DENV-infected brain with a significant increase in mRNA for CD8 but not CD4 suggesting this infiltrate is likely CD8+ but not CD4+ T-lymphocytes. This increase in T-cell infiltration was not affected by the lack of SK1. Overall, DENV-infection in the brain induces IFN and T-cell responses but does not influence the SK/S1P axis. In contrast to our observations in vitro, SK1 has no major influence on these responses following DENV-infection in the mouse brain.Wisam H. Al-Shujairi, Jennifer N. Clarke, Lorena T. Davies, Mohammed Alsharifi, Stuart M. Pitson, Jillian M. Car

    CLEC5A Regulates Japanese Encephalitis Virus-Induced Neuroinflammation and Lethality

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    CLEC5A/MDL-1, a member of the myeloid C-type lectin family expressed on macrophages and neutrophils, is critical for dengue virus (DV)-induced hemorrhagic fever and shock syndrome in Stat1−/− mice and ConA-treated wild type mice. However, whether CLEC5A is involved in the pathogenesis of viral encephalitis has not yet been investigated. To investigate the role of CLEC5A to regulate JEV-induced neuroinflammation, antagonistic anti-CLEC5A mAb and CLEC5A-deficient mice were generated. We find that Japanese encephalitis virus (JEV) directly interacts with CLEC5A and induces DAP12 phosphorylation in macrophages. In addition, JEV activates macrophages to secrete proinflammatory cytokines and chemokines, which are dramatically reduced in JEV-infected Clec5a−/− macrophages. Although blockade of CLEC5A cannot inhibit JEV infection of neurons and astrocytes, anti-CLEC5A mAb inhibits JEV-induced proinflammatory cytokine release from microglia and prevents bystander damage to neuronal cells. Moreover, JEV causes blood-brain barrier (BBB) disintegrity and lethality in STAT1-deficient (Stat1−/−) mice, whereas peripheral administration of anti-CLEC5A mAb reduces infiltration of virus-harboring leukocytes into the central nervous system (CNS), restores BBB integrity, attenuates neuroinflammation, and protects mice from JEV-induced lethality. Moreover, all surviving mice develop protective humoral and cellular immunity against JEV infection. These observations demonstrate the critical role of CLEC5A in the pathogenesis of Japanese encephalitis, and identify CLEC5A as a target for the development of new treatments to reduce virus-induced brain damage

    Synthetic Nanoparticles for Vaccines and Immunotherapy

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    The immune system plays a critical role in our health. No other component of human physiology plays a decisive role in as diverse an array of maladies, from deadly diseases with which we are all familiar to equally terrible esoteric conditions: HIV, malaria, pneumococcal and influenza infections; cancer; atherosclerosis; autoimmune diseases such as lupus, diabetes, and multiple sclerosis. The importance of understanding the function of the immune system and learning how to modulate immunity to protect against or treat disease thus cannot be overstated. Fortunately, we are entering an exciting era where the science of immunology is defining pathways for the rational manipulation of the immune system at the cellular and molecular level, and this understanding is leading to dramatic advances in the clinic that are transforming the future of medicine.1,2 These initial advances are being made primarily through biologic drugs– recombinant proteins (especially antibodies) or patient-derived cell therapies– but exciting data from preclinical studies suggest that a marriage of approaches based in biotechnology with the materials science and chemistry of nanomaterials, especially nanoparticles, could enable more effective and safer immune engineering strategies. This review will examine these nanoparticle-based strategies to immune modulation in detail, and discuss the promise and outstanding challenges facing the field of immune engineering from a chemical biology/materials engineering perspectiveNational Institutes of Health (U.S.) (Grants AI111860, CA174795, CA172164, AI091693, and AI095109)United States. Department of Defense (W911NF-13-D-0001 and Awards W911NF-07-D-0004

    The Endoplasmic Reticulum Stress Response in Neuroprogressive Diseases: Emerging Pathophysiological Role and Translational Implications

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    The endoplasmic reticulum (ER) is the main cellular organelle involved in protein synthesis, assembly and secretion. Accumulating evidence shows that across several neurodegenerative and neuroprogressive diseases, ER stress ensues, which is accompanied by over-activation of the unfolded protein response (UPR). Although the UPR could initially serve adaptive purposes in conditions associated with higher cellular demands and after exposure to a range of pathophysiological insults, over time the UPR may become detrimental, thus contributing to neuroprogression. Herein, we propose that immune-inflammatory, neuro-oxidative, neuro-nitrosative, as well as mitochondrial pathways may reciprocally interact with aberrations in UPR pathways. Furthermore, ER stress may contribute to a deregulation in calcium homoeostasis. The common denominator of these pathways is a decrease in neuronal resilience, synaptic dysfunction and even cell death. This review also discusses how mechanisms related to ER stress could be explored as a source for novel therapeutic targets for neurodegenerative and neuroprogressive diseases. The design of randomised controlled trials testing compounds that target aberrant UPR-related pathways within the emerging framework of precision psychiatry is warranted
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