95 research outputs found

    The iRhom2/ADAM17 Axis Attenuates Bacterial Uptake by Phagocytes in a Cell Autonomous Manner

    Get PDF
    Uptake of bacteria by phagocytes is a crucial step in innate immune defence. Members of the disintegrin and metalloproteinase (ADAM) family critically control the immune response by limited proteolysis of surface expressed mediator molecules. Here, we investigated the significance of ADAM17 and its regulatory adapter molecule iRhom2 for bacterial uptake by phagocytes. Inhibition of metalloproteinase activity led to increased phagocytosis of pHrodo labelled Gram-negative and -positive bacteria (E. coli and S. aureus, respectively) by human and murine monocytic cell lines or primary phagocytes. Bone marrow-derived macrophages showed enhanced uptake of heat-inactivated and living E. coli when they lacked either ADAM17 or iRhom2 but not upon ADAM10-deficiency. In monocytic THP-1 cells, corresponding short hairpin RNA (shRNA)-mediated knockdown confirmed that ADAM17, but not ADAM10, promoted phagocytosis of E. coli. The augmented bacterial uptake occurred in a cell autonomous manner and was accompanied by increased release of the chemokine CXCL8, less TNFα release and only minimal changes in the surface expression of the receptors TNFR1, TLR6 and CD36. Inhibition experiments indicated that the enhanced bacterial phagocytosis after ADAM17 knockdown was partially dependent on TNFα-activity but not on CXCL8. This novel role of ADAM17 in bacterial uptake needs to be considered in the development of ADAM17 inhibitors as therapeutics

    Система генерации отчетов САПР бортового программного обеспечения космических аппаратов

    Get PDF
    Целью работы является проектирование и реализация системы генерации отчетов в САПР БПО. В ходе работы разработана система, призванная автоматизировать создание отчетов по данным, которыми оперирует САПР БПО. В частности, система позволяет генерировать отчеты по ресурсам, отчет-Д по отображению формата кадров телеметрической информации и документ "Исходные данные на изделие". В отчетах заполняются таблицы по использованию аппаратных ресурсов спутника бортовым программным обеспечением. Отчеты формируются в качестве документов Microsoft Word и Excel с требуемым форматированием.The aim of the work is to design and implement the report generating system in CAD BS. As the result of the work, the system that automates the creation of reports was developed. Particularly, the system allows to generate resource reports, “Report-D” that shows formats of the telemetry data and the document “Satellite Source Data”. The system fills the tables describing satellite hardware resource distribution by on-board software. The reports are formed as Microsoft Word and Excel documents with required formatting

    Tetanus toxin Hc fragment induces the formation of ceramide platforms and protects neuronal cells against oxidative stress

    Get PDF
    Tetanus toxin (TeTx) is the protein, synthesized by the anaerobic bacteria Clostridium tetani, which causes tetanus disease. TeTx gains entry into target cells by means of its interaction with lipid rafts, which are membrane domains enriched in sphingomyelin and cholesterol. However, the exact mechanism of host membrane binding remains to be fully established. In the present study we used the recombinant carboxyl terminal fragment from TeTx (Hc-TeTx), the domain responsible for target neuron binding, showing that Hc-TeTx induces a moderate but rapid and sustained increase in the ceramide/sphingomyelin ratio in primary cultures of cerebellar granule neurons and in NGF-differentiated PC12 cells, as well as induces the formation of ceramide platforms in the plasma membrane. The mentioned increase is due to the promotion of neutral sphingomyelinase activity and not to the de novo synthesis, since GW4869, a specific neutral sphingomyelinase inhibitor, prevents neutral sphingomyelinase activity increase and formation of ceramide platforms. Moreover, neutral sphingomyelinase inhibition with GW4869 prevents Hc-TeTx-triggered signaling (Akt phosphorylation), as well as the protective effect of Hc-TeTx on PC12 cells subjected to oxidative stress, while siRNA directed against nSM2 prevents protection by Hc-TeTx of NSC-34 cells against oxidative insult. Finally, neutral sphingomyelinase activity seems not to be related with the internalization of Hc-TeTx into PC12 cells. Thus, the presented data shed light on the mechanisms triggered by TeTx after membrane binding, which could be related with the events leading to the neuroprotective action exerted by the Hc-TeTx fragment

    Phagozytose-induzierter direkter Zelltod und Bystander-Kill von Monozyten

    No full text

    Rhinoviruses infect epithelial cells via membrane rafts

    No full text
    corecore