Calcium-sensing soluble adenylyl cyclase mediates TNF signal transduction in human neutrophils. Academic Article uri icon

Overview

abstract

  • Through chemical screening, we identified a pyrazolone that reversibly blocked the activation of phagocyte oxidase (phox) in human neutrophils in response to tumor necrosis factor (TNF) or formylated peptide. The pyrazolone spared activation of phox by phorbol ester or bacteria, bacterial killing, TNF-induced granule exocytosis and phox assembly, and endothelial transmigration. We traced the pyrazolone's mechanism of action to inhibition of TNF-induced intracellular Ca2+ elevations, and identified a nontransmembrane ("soluble") adenylyl cyclase (sAC) in neutrophils as a Ca2+-sensing source of cAMP. A sAC inhibitor mimicked the pyrazolone's effect on phox. Both compounds blocked TNF-induced activation of Rap1A, a phox-associated guanosine triphosphatase that is regulated by cAMP. Thus, TNF turns on phox through a Ca2+-triggered, sAC-dependent process that may involve activation of Rap1A. This pathway may offer opportunities to suppress oxidative damage during inflammation without blocking antimicrobial function.

publication date

  • July 25, 2005

Research

keywords

  • Adenylyl Cyclases
  • Calcium Signaling
  • Neutrophil Activation
  • Neutrophils
  • Receptors, Calcium-Sensing
  • Tumor Necrosis Factor-alpha

Identity

PubMed Central ID

  • PMC2213086

Scopus Document Identifier

  • 23744489145

Digital Object Identifier (DOI)

  • 10.1084/jem.20050778

PubMed ID

  • 16043520

Additional Document Info

volume

  • 202

issue

  • 3