Caspase-1-independent interleukin-1β is required for clearance of Bordetella pertussis infections and whole-cell vaccine-mediated immunity

PLoS One. 2014 Sep 8;9(9):e107188. doi: 10.1371/journal.pone.0107188. eCollection 2014.

Abstract

Whooping cough remains a significant disease worldwide and its re-emergence in highly vaccinated populations has been attributed to a combination of imperfect vaccines and evolution of the pathogen. The focus of this study was to examine the role of IL-1α/β and the inflammasome in generation of the interleukin-1 (IL-1) response, which is required for the clearance of Bordetella pertussis. We show that IL-1β but not IL-1α is required for mediating the clearance of B. pertussis from the lungs of mice. We further found that IL-1β and IL-1R deficient mice, compared to wild-type, have similar but more persistent levels of inflammation, characterized by immune cell infiltration, with significantly increased IFNγ and a normal IL-17A response during B. pertussis infection. Contrary to expectations, the cleavage of precursor IL-1β to its mature form did not require caspase-1 during primary infections within the lung despite being required by bone marrow-derived macrophages exposed to live bacteria. We also found that the caspase-1 inflammasome was not required for protective immunity against a B. pertussis challenge following vaccination with heat-killed whole cell B. pertussis, despite IL-1R signaling being required. These findings demonstrate that caspase-1-independent host factors are involved in the processing of protective IL-1β responses that are critical for bacterial clearance and vaccine-mediated immunity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adaptive Immunity
  • Animals
  • Bordetella Infections / immunology*
  • Bordetella Infections / pathology
  • Bordetella pertussis / immunology
  • Bordetella pertussis / physiology*
  • Caspase 1 / metabolism
  • Interleukin-1beta / metabolism*
  • Mice
  • Pertussis Vaccine / immunology*
  • Signal Transduction

Substances

  • Interleukin-1beta
  • Pertussis Vaccine
  • Caspase 1