27 research outputs found

    TRAIL Dependent Fratricidal Killing of gp120 Primed Hepatocytes by HCV Core Expressing Hepatocytes

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    The mechanism by which HIV and HCV cooperatively accelerate hepatocyte damage is not clearly understood; however, each virus affects the TRAIL: TRAIL- receptor system. We, therefore, questioned whether the independent effects of HCV and HIV combine to synergistically result in TRAIL dependent hepatocyte killing. We describe that Huh7 hepatocytes treated with HIV gp120 results in both increase TRAIL-R2 expression and an acquired sensitivity to TRAIL mediated killing. Moreover HCV infection and HCV core expression alone in Huh7 cells upregulates TRAIL. Co-incubation of HIV gp120 primed hepatocytes with HCV core expressing hepatocytes results in the selective death of the HIV gp120 primed hepatocytes that is selectively blocked by TRAIL–R2-Fc fusion protein. Liver biopsies from HIV mono-infected patients have increased TRAIL-R2; biopsies from HCV infected patients have increased TRAIL, while co-infected liver biopsies have increased PARP cleavage within hepatocytes indicating enhanced apoptosis. These findings suggest a pathogenic model to understand why HIV/HCV co-infection accelerates liver injury

    A Single-Chain-Based Hexavalent CD27 Agonist Enhances T Cell Activation and Induces Anti-Tumor Immunity

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    Tumor necrosis factor receptor superfamily member 7 (TNFRSF7, CD27), expressed primarily by T cells, and its ligand CD27L (TNFSF7, CD70) provide co-stimulatory signals that boost T cell activation, differentiation, and survival. Agonistic stimulation of CD27 is therefore a promising therapeutic concept in immuno-oncology intended to boost and sustain T cell driven anti-tumor responses. Endogenous TNFSF/TNFRSF-based signal transmission is a structurally well-defined event that takes place during cell-to-cell-based contacts. It is well-established that the trimeric-trivalent TNFSF-receptor binding domain (TNFSF-RBD) exposed by the conducting cell and the resulting multi-trimer-based receptor clustering on the receiving cell are essential for agonistic signaling. Therefore, we have developed HERA-CD27L, a novel hexavalent TNF receptor agonist (HERA) targeting CD27 and mimicking the natural signaling concept. HERA-CD27L is composed of a trivalent but single-chain CD27L-receptor-binding-domain (scCD27L-RBD) fused to an IgG1 derived silenced Fc-domain serving as dimerization scaffold. The hexavalent agonist significantly boosted antigen-specific T cell responses while having no effect on non-specific T cells and was superior over stabilized recombinant trivalent CD27L. In addition, HERA-CD27L demonstrated potent single-agent anti-tumor efficacy in two different syngeneic tumor models, MC38-CEA and CT26wt. Furthermore, the combination of HERA-CD27L and an anti-PD-1 antibody showed additive anti-tumor effects highlighting the importance of both T cell activation and checkpoint inhibition in anti-tumor immunity. In this manuscript, we describe the development of HERA-CD27L, a true CD27 agonist with a clearly defined forward-signaling mechanism of action

    Модернизация автоматизированной системы блока стабилизации давления магистрального насосного агрегата на нефтеперекачивающей станции

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    Объектом исследования является блок стабилизации давления магистрального насосного агрегата. Цель работы – модернизация автоматизированной системы блока стабилизации давления магистрального трубопровода нефтеперекачивающей станции с использованием ПЛК, на основе выбранной SCADA-системы. В данном проекте была разработана система контроля и управления технологическим процессом на базе промышленных контроллеров Modicon M340 BMXP34 2020, с применением SCADA-системы.The object of investigation is the pressure stabilization unit of the main pump unit. The purpose of the work is the modernization of the automated system for stabilizing the pressure of the main pipeline of the oil pumping station using PLCs, based on the SCADA system chosen. In this project, a system for monitoring and controlling the process was developed on the basis of industrial controllers Modicon M340 BMXP34 2020, using a SCADA system

    Apoptosis and Cancer Therapy: From Cutting-edge Science to Novel Therapeutic Concepts

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    The death ligand TRAIL was discovered just over 10 years ago. In this chapter, we summarize the most important findings on the biochemistry, biology and potential therapeutic applicability of this promising novel cytokine. We address a number of eminent questions. How does TRAIL apoptosis signaling work and what is special about it? Why is this member of the tumor necrosis factor family of cytokines so interesting for cancer researchers and immunologists? What is the physiological role of the TRAIL\u2013TRAIL receptor system? We cannot provide full answers to all of these questions; however, we intend to point out to the reader the most important unsolved scientific questions regarding the biology of this fascinating cytokine and its receptors

    Proteasome inhibition sensitizes hepatocellular carcinoma cells, but not human hepatocytes, to TRAIL

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    TRAIL exhibits potent anti-tumor activity on systemic administration in mice. Because of its proven in vivo efficacy, TRAIL may serve as a novel anti-neoplastic drug. However, approximately half of the tumor cell lines tested so far are TRAIL resistant, and potential toxic side effects of certain recombinant forms of TRAIL on human hepatocytes have been described. Pretreatment with the proteasome inhibitor MG132 and PS-341 rendered TRAIL-resistant hepatocellular carcinoma (HCC) cell lines but not primary human hepatocytes sensitive for TRAIL-induced apoptosis. We investigated the different levels of possible MG132-induced interference with resistance to apoptotic signal transduction. Although proteasome inhibition efficiently suppressed nuclear factor-kappaB (NF-κB) activity, specific suppression of NF-κB by mutIκBα failed to sensitize TRAIL-resistant cell lines for TRAIL-induced apoptosis. In contrast to the previously reported mechanism of sensitization by 5-fluorouracil (5-FU), cellular FLICE-inhibitory protein (cFLIP)L and cFLIPS were markedly upregulated in the TRAIL death inducing signaling complex (DISC) by proteasome inhibitor pretreatment. Compared with 5-FU pretreatment, caspase-8 was more efficiently recruited to the DISC in MG132 pretreated cells despite the presence of fewer death receptors and more cFLIP in the DISC. But downregulation of cFLIP by short interference RNA (siRNA) further sensitized the HCC cell lines. In conclusion, these results show that otherwise chemotherapy-resistant tumor cells can be sensitized for TRAIL-induced apoptosis at the DISC level in the presence of high levels of cFLIP, which suggests the existence of an additional factor that modulates the interaction of FADD and the TRAIL death receptors. Of clinical relevance, proteasome inhibitors sensitize HCC cells but not primary human hepatocytes for TRAIL-induced apoptosis. Copyright © 2005 by the American Association for the Study of Liver Diseases

    TRAIL/bortezomib cotreatment is potentially hepatotoxic but induces cancer-specific apoptosis within a therapeutic window

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    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) represents a novel promising anticancer biotherapeutic. However, TRAIL-resistant tumor cells require combinatorial regimens to sensitize tumor but not normal cells for TRAIL-induced apoptosis. Here, we investigated the mechanism of the synergistic antitumor effect of bortezomib in combination with TRAIL in hepatoma, colon, and pancreatic cancer cells in comparison to the toxicity in primary human hepatocytes (PHH). TRAIL cotreatment at high but clinically relevant concentrations of bortezomib caused toxicity in PHH which potentially limits the clinical applicability of bortezomib/TRAIL cotreatment. However, at low concentrations of bortezomib TRAIL-resistant hepatoma, colon and pancreatic cancer cell lines but not PHH were efficiently sensitized for TRAIL-induced apoptosis. RNA interference and TRAIL receptor blockage experiments revealed that in bortezomib-treated hepatoma cells TRAIL-R1/TRAIL-R2 up-regulation, enhanced TRAIL DISC formation and cFLIPL down-regulation in addition to accumulation of Bak cooperatively sensitized for TRAIL. Bim, although accumulated upon bortezomib treatment, did not play a causal role for TRAIL sensitization in Hep3b cells. Combined treatment with bortezomib and TRAIL massively reduced the clonogenic capacity of hepatoma cells in vitro. Surviving clones could be resensitized for repeated TRAIL treatment. Conclusion: Bortezomib/TRAIL cotreatment bears the risk of severe hepatotoxicity at high but clinically relevant concentrations of bortezomib. However, within a wide therapeutic window bortezomib sensitized different cancer cells but not PHH for TRAIL-induced apoptosis. Copyright \uc2\ua9 2007 by the American Association for the Study of Liver Diseases

    Performance studies of new optics for the time-of-flight detector of the AFP project

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    We present the results of performance studies of the upgraded optical part of the time-of-flight subdetector prototype for the AFP (ATLAS Forward Proton) detector obtained during the test campaign in a synchrotron test-beam facility with 5 GeV electrons at the DESY laboratory (Hamburg, Germany) in June 2019. The detection of the particle arrival time is based on generation of Cherenkov light in an L-shaped fused silica bar. In the previous version of the ToF, all bars were made of two pieces (radiator and light guide) glued together with a dedicated glue (Epotek 305). This solution suffers from additional radiation damage of glue. We adopted a new technique of bar production without the need of glue. The new bars have a higher optical throughput by a factor of 1.6, reduced fragility, and better geometrical precision
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