52 research outputs found
TNF-α Regulates Human Plasmacytoid Dendritic Cells by Suppressing IFN-α Production and Enhancing T Cell Activation
Human plasmacytoid dendritic cells (pDCs) play a vital role in modulating immune responses. They can produce massive amounts of type I IFNs in response to nucleic acids via TLRs, but they are also known to possess weak Ag-presenting properties inducing CD4+ T cell activation. Previous studies showed a cross-regulation between TNF-α and IFN-α, but many questions remain about the effect of TNF-α in regulating human pDCs. In this study, we showed that TNF-α significantly inhibited the secretion of IFN-α and TNF-α of TLR-stimulated pDCs. Instead, exogenous TNF-α promoted pDC maturation by upregulating costimulatory molecules and chemokine receptors such as CD80, CD86, HLA-DR, and CCR7. Additionally, RNA sequencing analysis showed that TNF-α inhibited IFN-α and TNF-α production by downregulating IRF7 and NF-κB pathways, while it promoted Ag processing and presentation pathways as well as T cell activation and differentiation. Indeed, TNF-α–treated pDCs induced in vitro higher CD4+ T cell proliferation and activation, enhancing the production of Th1 and Th17 cytokines. In conclusion, TNF-α favors pDC maturation by switching their main role as IFN-α–producing cells to a more conventional dendritic cell phenotype. The functional status of pDCs might therefore be strongly influenced by their overall inflammatory environment, and TNF-α might regulate IFN-α–mediated aspects of a range of autoimmune and inflammatory diseases
Investigating the Inter-Tube Conduction Mechanism in Polycarbonate Nanocomposites Prepared with Conductive Polymer-Coated Carbon Nanotubes
Development and characterization of a novolac resin/BaTiO3 nanoparticles composite system
Evaluation of dielectric behaviour of particulate composites consisting of polymeric matrix and conductive filler
DC and AC conductivity in polymeric particulate composites of epoxy resin and metal particles
Dielectric dispersion and ac conductivity in - Iron particles loaded: Polymer composites
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