Recognition of Streptococcus pneumoniae by the innate immune system

Cell Microbiol. 2012 Apr;14(4):460-6. doi: 10.1111/j.1462-5822.2011.01746.x. Epub 2012 Feb 8.


Streptococcus pneumoniae is both a frequent colonizer of the upper respiratory tract and a leading cause of life-threatening infections such as pneumonia, meningitis and sepsis. The innate immune system is critical for the control of colonization and for defence during invasive disease. Initially, pneumococci are recognized by different sensors of the innate immune system called pattern recognition receptors (PRRs), which control most subsequent host defence pathways. These PRRs include the transmembrane Toll-like receptors (TLRs) as well as the cytosolic NOD-like receptors (NLRs) and DNA sensors. Recognition of S. pneumoniae by members of these PRR families regulates the production of inflammatory mediators that orchestrate the following immune response of infected as well as neighbouring non-infected cells, stimulates the recruitment of immune cells such as neutrophils and macrophages, and shapes the adaptive immunity. This review summarizes the current knowledge of the function of different PRRs in S. pneumoniae infection.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cytosol / immunology
  • Host-Pathogen Interactions
  • Humans
  • Immunity, Innate*
  • Inflammasomes / immunology
  • Inflammation Mediators / immunology
  • Interferons / immunology
  • Interleukins / immunology
  • Macrophages / immunology
  • Macrophages / microbiology
  • Mice
  • Nod2 Signaling Adaptor Protein / immunology
  • Pneumococcal Infections / immunology*
  • Pneumococcal Infections / microbiology
  • Streptococcus pneumoniae / immunology*
  • Toll-Like Receptors / immunology


  • Inflammasomes
  • Inflammation Mediators
  • Interleukins
  • NOD2 protein, human
  • Nod2 Signaling Adaptor Protein
  • Toll-Like Receptors
  • Interferons