Innate recognition of intracellular pathogens: detection and activation of the first line of defense

APMIS. 2009 May;117(5-6):323-37. doi: 10.1111/j.1600-0463.2009.02456.x.


The innate immune system constitutes the first line of defense against infections and is also important for initiating the development of an adaptive immune response. The innate immune system recognizes microbial infection through germline-encoded pattern recognition receptors, which are responsible for decoding the microbial fingerprint and activating an appropriate response against the invading pathogen. In this review, we present and discuss current knowledge on how the innate immune system recognizes intracellular pathogens, activates intracellular signaling, induces gene expression, and orchestrates the microbicidal response against pathogens with a habitat within host cells.

Publication types

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

MeSH terms

  • Animals
  • Cells / microbiology*
  • Cells / parasitology*
  • Cells / virology
  • DEAD-box RNA Helicases / physiology
  • DNA-Binding Proteins / physiology
  • Gene Expression Regulation
  • Host-Parasite Interactions / immunology*
  • Humans
  • Immunity, Innate*
  • Immunologic Memory
  • Infections / genetics
  • Infections / immunology
  • Inflammation / genetics
  • Inflammation / immunology
  • Nod Signaling Adaptor Proteins / physiology
  • RNA-Binding Proteins
  • Receptors, Pattern Recognition / physiology
  • Signal Transduction / physiology
  • Toll-Like Receptors / physiology


  • DNA-Binding Proteins
  • Nod Signaling Adaptor Proteins
  • RNA-Binding Proteins
  • Receptors, Pattern Recognition
  • Toll-Like Receptors
  • ZBP1 protein, human
  • DEAD-box RNA Helicases