Genome-wide expression profiling identifies type 1 interferon response pathways in active tuberculosis

PLoS One. 2012;7(9):e45839. doi: 10.1371/journal.pone.0045839. Epub 2012 Sep 21.

Abstract

Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb), remains the leading cause of mortality from a single infectious agent. Each year around 9 million individuals newly develop active TB disease, and over 2 billion individuals are latently infected with M.tb worldwide, thus being at risk of developing TB reactivation disease later in life. The underlying mechanisms and pathways of protection against TB in humans, as well as the dynamics of the host response to M.tb infection, are incompletely understood. We carried out whole-genome expression profiling on a cohort of TB patients longitudinally sampled along 3 time-points: during active infection, during treatment, and after completion of curative treatment. We identified molecular signatures involving the upregulation of type-1 interferon (α/β) mediated signaling and chronic inflammation during active TB disease in an Indonesian population, in line with results from two recent studies in ethnically and epidemiologically different populations in Europe and South Africa. Expression profiles were captured in neutrophil-depleted blood samples, indicating a major contribution of lymphocytes and myeloid cells. Expression of type-1 interferon (α/β) genes mediated was also upregulated in the lungs of M.tb infected mice and in infected human macrophages. In patients, the regulated gene expression-signature normalized during treatment, including the type-1 interferon mediated signaling and a concurrent opposite regulation of interferon-gamma. Further analysis revealed IL15RA, UBE2L6 and GBP4 as molecules involved in the type-I interferon response in all three experimental models. Our data is highly suggestive that the innate immune type-I interferon signaling cascade could be used as a quantitative tool for monitoring active TB disease, and provide evidence that components of the patient's blood gene expression signature bear similarities to the pulmonary and macrophage response to mycobacterial infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Case-Control Studies
  • Cell Line
  • Cluster Analysis
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation
  • Genome, Human
  • Host-Pathogen Interactions
  • Humans
  • Indonesia
  • Interferon Type I / genetics*
  • Interferon Type I / metabolism
  • Longitudinal Studies
  • Lung / metabolism
  • Male
  • Metabolic Networks and Pathways / genetics
  • Metabolic Networks and Pathways / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mycobacterium tuberculosis / physiology*
  • Oligonucleotide Array Sequence Analysis
  • Transcriptome*
  • Tuberculosis, Pulmonary / blood*
  • Tuberculosis, Pulmonary / genetics
  • Tuberculosis, Pulmonary / immunology

Substances

  • Interferon Type I

Grants and funding

The authors gratefully acknowledge the support of the following organizations: the Netherlands’ Organization of Scientific Research (NWO); the Royal Netherlands’ Academy of Arts and Sciences (KNAW); WOTRO/NACCAP; the Bill and Melinda Gates Foundation Grand Challenges in Global Health (grant GC6#74); the Netherlands Leprosy Relief Foundation; the Q.M. Gastmann Wichers Foundation. The research also received funding from the European Union's Seventh Framework Programme [FP7/2007–2013] for projects NEWTBVAC; IDEA; and ADITEC (No: 280873). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.