Pathogen recognition by the innate immune system

Int Rev Immunol. 2011 Feb;30(1):16-34. doi: 10.3109/08830185.2010.529976.


Microbial infection initiates complex interactions between the pathogen and the host. Pathogens express several signature molecules, known as pathogen-associated molecular patterns (PAMPs), which are essential for survival and pathogenicity. PAMPs are sensed by evolutionarily conserved, germline-encoded host sensors known as pathogen recognition receptors (PRRs). Recognition of PAMPs by PRRs rapidly triggers an array of anti-microbial immune responses through the induction of various inflammatory cytokines, chemokines and type I interferons. These responses also initiate the development of pathogen-specific, long-lasting adaptive immunity through B and T lymphocytes. Several families of PRRs, including Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), NOD-like receptors (NLRs), and DNA receptors (cytosolic sensors for DNA), are known to play a crucial role in host defense. In this review, we comprehensively review the recent progress in the field of PAMP recognition by PRRs and the signaling pathways activated by PRRs.

Publication types

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

MeSH terms

  • Adaptive Immunity
  • Animals
  • Antigens / immunology*
  • Antigens / metabolism
  • Apicomplexa
  • B-Lymphocytes / immunology
  • Bacteria
  • Cytokines / immunology
  • Fungi
  • Host-Pathogen Interactions / immunology*
  • Humans
  • Immunity, Innate*
  • Infections / immunology*
  • Inflammasomes / immunology
  • Inflammasomes / metabolism
  • Interferon Type I / immunology
  • Mice
  • Receptors, Cell Surface / immunology
  • Receptors, Cell Surface / metabolism
  • Signal Transduction / immunology*
  • T-Lymphocytes / immunology
  • Toll-Like Receptors / immunology
  • Toll-Like Receptors / metabolism


  • Antigens
  • Cytokines
  • DNA receptor
  • Inflammasomes
  • Interferon Type I
  • Receptors, Cell Surface
  • Toll-Like Receptors