Caspase-1 dependent macrophage death induced by Burkholderia pseudomallei

Cell Microbiol. 2005 Oct;7(10):1447-58. doi: 10.1111/j.1462-5822.2005.00569.x.

Abstract

Burkholderia pseudomallei is the causative agent for melioidosis, an infectious disease endemic in South-east Asia and northern Australia. Infection can result in a wide spectrum of clinical outcomes, including asymtomatic, acute or chronic conditions. The ability of the bacteria to survive intracellularly within phagocytes and non-phagocytes is postulated to help this pathogen persist in the body during latent chronic conditions. In some Gram-negative bacteria, such as Shigella and Salmonella, the ability to evade macrophage killing involves inducing rapid macrophage cell death. In several of these instances, these bacteria activate cellular caspase-1 to induce cell death, which is increasingly described to exhibit features more characteristic of oncosis than classical apoptosis. We found that B. pseudomallei is also capable of inducing caspase-1 dependent death in macrophages and this process requires a functional bsa Type III Secretion System (TTSS). Bacterial internalization and pore formation in the cell membrane is necessary for death. Furthermore, cell death is accompanied by the release of IL-1beta and IL-18. We believe that this novel description of macrophage death induced by B. pseudomallei could shed light on the pathogenesis of the bacteria in disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Burkholderia pseudomallei / pathogenicity*
  • Caspase 1 / metabolism*
  • Cell Death*
  • Cell Line
  • Cells, Cultured
  • Dendritic Cells / microbiology
  • Humans
  • Interleukin-1 / metabolism
  • Interleukin-18 / metabolism
  • Macrophages / microbiology*
  • Mice
  • Monocytes / microbiology

Substances

  • Interleukin-1
  • Interleukin-18
  • Caspase 1