Regulation of IL-10 secretion after phagocytosis of Mycobacterium tuberculosis by human monocytic cells

Cytokine. 2000 May;12(5):483-6. doi: 10.1006/cyto.1999.0586.

Abstract

Downregulation of pro-inflammatory events in the immune response to Mycobacterium tuberculosis is critical to prevent host tissue injury. Interleukin (IL-)10 is an important anti-inflammatory cytokine secreted in human tuberculosis but little is known about the control of such IL-10 release. Using an established cellular model, we measured IL-10 secretion after phagocytosis of M. tuberculosis. Phagocytosis of M. tuberculosis but not of inert latex beads by human monocytic (THP-1) cells resulted in IL-10 secretion maximal at 24 h. The magnitude and kinetics of IL-10 secretion were distinct from IL-10 secretion after phagocytosis of yeast-derived zymosan and depended on transcriptional activity and protein synthesis in infected monocytes. IL-10 secretion was decreased in a dose-dependent manner by specific inhibitors of tyrosine kinases, protein kinase (PK) C and PKA. Inhibition of more than one pathway did not result in further synergistic or additive reduction in IL-10 secretion. Finally, specific neutralising antibody directed against IL-10 demonstrated that IL-10 secreted by infected monocytic cells did not block autologous IL-8 secretion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbazoles*
  • Cell Line
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors
  • Enzyme Inhibitors / pharmacology
  • Genistein / pharmacology
  • Humans
  • Indoles / pharmacology
  • Interleukin-10 / metabolism*
  • Interleukin-8 / metabolism
  • Mycobacterium tuberculosis / immunology*
  • Naphthalenes / pharmacology
  • Phagocytosis / immunology*
  • Protein Kinase C / antagonists & inhibitors
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Pyrroles / pharmacology

Substances

  • Carbazoles
  • Enzyme Inhibitors
  • Indoles
  • Interleukin-8
  • Naphthalenes
  • Pyrroles
  • Interleukin-10
  • KT 5720
  • Genistein
  • Protein-Tyrosine Kinases
  • Cyclic AMP-Dependent Protein Kinases
  • Protein Kinase C
  • calphostin C