Biomarkers of inflammation, immunosuppression and stress with active disease are revealed by metabolomic profiling of tuberculosis patients

PLoS One. 2012;7(7):e40221. doi: 10.1371/journal.pone.0040221. Epub 2012 Jul 23.

Abstract

Although tuberculosis (TB) causes more deaths than any other pathogen, most infected individuals harbor the pathogen without signs of disease. We explored the metabolome of >400 small molecules in serum of uninfected individuals, latently infected healthy individuals and patients with active TB. We identified changes in amino acid, lipid and nucleotide metabolism pathways, providing evidence for anti-inflammatory metabolomic changes in TB. Metabolic profiles indicate increased activity of indoleamine 2,3 dioxygenase 1 (IDO1), decreased phospholipase activity, increased abundance of adenosine metabolism products, as well as indicators of fibrotic lesions in active disease as compared to latent infection. Consistent with our predictions, we experimentally demonstrate TB-induced IDO1 activity. Furthermore, we demonstrate a link between metabolic profiles and cytokine signaling. Finally, we show that 20 metabolites are sufficient for robust discrimination of TB patients from healthy individuals. Our results provide specific insights into the biology of TB and pave the way for the rational development of metabolic biomarkers for TB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / metabolism
  • Case-Control Studies
  • Cluster Analysis
  • Female
  • Humans
  • Immune Tolerance*
  • Indoleamine-Pyrrole 2,3,-Dioxygenase / metabolism
  • Inflammation / metabolism
  • Kynurenine / biosynthesis
  • Male
  • Metabolomics*
  • Stress, Physiological*
  • Tuberculosis, Pulmonary / enzymology
  • Tuberculosis, Pulmonary / immunology*
  • Tuberculosis, Pulmonary / metabolism*
  • Tuberculosis, Pulmonary / physiopathology

Substances

  • Biomarkers
  • Indoleamine-Pyrrole 2,3,-Dioxygenase
  • Kynurenine

Grants and funding

This work was supported by a floating grant from the Max Planck Society to SHEK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.