T cells upon activation promote endothelin 1 production in monocytes via IFN-γ and TNF-α

Abstract

Endothelin 1 (ET-1), mainly produced from vascular endothelial cells, induces vasoconstriction in physiological conditions. The endothelin receptor antagonist is among the most effective agents for pulmonary hypertension. However, little is known about the production source of ET-1 in inflammation and immunity. Here, we studied whether T cell-mediated ET-1 production system exists and operates independent of the production system in vascular endothelial cells. ET-1 production was readily detectable in the culture supernatant of human PBMCs and murine spleen cells stimulated with anti-CD3 antibody. Immunocytostaining showed that ET-1-producing cells emerged only in PBMCs stimulated with anti-CD3 antibody. Using the Transwell system, both murine and human monocytes sorted with magnetic beads in the inner chamber produced ET-1 when T cells were activated with antigen or anti-CD3 antibody in the outer chamber. This ET-1 production was inhibited by anti-IFN-γ and/or TNF-α antibody. Furthermore, monocytes purified from ETflox/flox;Tie2-Cre( + ) mice, which conditionally lack ET-1 in hematopoietic stem cells and vascular endothelial cells, did not produce ET-1 even when stimulated by antigen-specific T cell activation. This study demonstrates the existence of an immune-mediated ET-1 production induced by T cells upon activation through IFN-γ and TNF-α.

Nitrogen‐Doped Metal‐Free Carbon Materials Derived from Cellulose as Electrocatalysts for the Oxygen Reduction Reaction

“…Figure 2b) are 73 and 65 mV dec À 1 for 10 N8/ HTC and 100 N8/HTC, respectively, indicating that for both samples the overall reaction rate is limited by the coverage of O 2 and O 2 À species. [26] The results are in line with those reported for other bio-based metal free N-doped carbon ORR electrocatalysts. [27] Since metal impurities, especially Fe, can induce a significant change in the electrocatalytic response of the carbon-based materials, [28] a control experiment was performed to confirm that the registered electrocatalytic ORR activity is not due to any metal impurities, which are difficult to detect using standard characterization methods.…”

Uniform, Assembled 4 nm Mn3O4 Nanoparticles as Efficient Water Oxidation Electrocatalysts at Neutral pH

“…[45] Figure 2b (2) and (3)), where j 0 , α, F, E 0 , R, and T are the exchange current density, transfer coefficient, Faraday constant, thermodynamic equilibrium potential, gas constant, and temperature, respectively. [57] The Tafel slopes of 74.5 and 72.2 mV dec −1 corresponds to 2.3 RT/F in Equation (3), meaning that the charge transfer coefficient (α) is 1. This result indicates that the reversible one-electron transfer step occurred prior to the rate determining step (RDS).…”

Stannites – A New Promising Class of Durable Electrocatalysts for Efficient Water Oxidation

“…The linear Tafel behavior could be observed until a current density of 11 mA/cm 2 for Cu 2 FeSnS 4 /NF in contrast to < 1 mA/cm 2 for Cu 2 FeSnS 4 /FTO, indicating that other effects such as surface coverage or electron/proton transport are influencing the catalytic behavior on FTO negatively at much lower current densities already. [63][64][65] Hence, the utilization of NF as an electrode substrate proved to be suitable to overcome these disadvantages to a certain extent.…”