R406 reduces lipopolysaccharide-induced neutrophil activation

Cell Immunol. 2024 Sep-Oct:403-404:104860. doi: 10.1016/j.cellimm.2024.104860. Epub 2024 Jul 26.

Abstract

Modulating SYK has been demonstrated to have impacts on pathogenic neutrophil responses in COVID-19. During sepsis, neutrophils are vital in early bacterial clearance but also contribute to the dysregulated immune response and organ injury when hyperactivated. Here, we evaluated the impact of R406, the active metabolite of fostamatinib, on neutrophils stimulated by LPS. We demonstrate that R406 was able to effectively inhibit NETosis, degranulation, ROS generation, neutrophil adhesion, and the formation of CD16low neutrophils that have been linked to detrimental outcomes in severe sepsis. Further, the neutrophils remain metabolically active, capable of releasing cytokines, perform phagocytosis, and migrate in response to IL-8. Taken together, this data provides evidence of the potential efficacy of utilizing fostamatinib in bacterial sepsis.

Keywords: Neutrophils; Sepsis; Spleen tyrosine kinase.

MeSH terms

  • Aminopyridines* / pharmacology
  • COVID-19 / immunology
  • Cell Adhesion / drug effects
  • Cell Degranulation / drug effects
  • Extracellular Traps / drug effects
  • Extracellular Traps / immunology
  • Extracellular Traps / metabolism
  • Humans
  • Imidazoles / pharmacology
  • Interleukin-8 / metabolism
  • Lipopolysaccharides* / immunology
  • Lipopolysaccharides* / pharmacology
  • Morpholines / pharmacology
  • Neutrophil Activation* / drug effects
  • Neutrophils* / drug effects
  • Neutrophils* / immunology
  • Neutrophils* / metabolism
  • Phagocytosis / drug effects
  • Pyridines / pharmacology
  • Pyrimidines / pharmacology
  • Reactive Oxygen Species / metabolism
  • Receptors, IgG / immunology
  • Receptors, IgG / metabolism
  • SARS-CoV-2 / immunology
  • Sepsis / drug therapy
  • Sepsis / immunology
  • Syk Kinase / metabolism

Substances

  • Lipopolysaccharides
  • Aminopyridines
  • Pyridines
  • fostamatinib
  • Syk Kinase
  • Reactive Oxygen Species
  • Morpholines
  • Interleukin-8
  • Pyrimidines
  • Receptors, IgG
  • Imidazoles
  • SYK protein, human