Encyclopedia of Signaling Molecules

2018 Edition
| Editors: Sangdun Choi

TLR4 (Toll-Like Receptor 4)

  • Jayalakshmi Krishnan
  • Muhammad Ayaz Anwar
  • Sangdun ChoiEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-67199-4_592


Historical Background

Immune responses are necessary to fight the infections incurred by various pathogens such as viruses, bacteria, and parasites in mammals (Kawai and Akira 2006). To sustain a regulated defense response, innate and adaptive immunity must harmonize and overcome the bacterial or viral challenge in which innate immunity precedes adaptive immunity. The innate and adaptive immune responses drastically differ in the type of cells involved, mode and time span of elimination, and in memorizing the specific signatures of the pathogens.

In 1989, Charles Janeway reported that a class of receptors, known as pattern recognition receptors (PRRs), recognize very specific patterns of chemical structures present on the invading pathogens, known as pathogen-associated molecular patterns (Janeway 1989). In 1996, the Hoffman group identified Toll genes, finding that...

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This work was supported by the National Research Foundation of Korea (NRF-2015R1A2A2A09001059).


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Jayalakshmi Krishnan
    • 1
  • Muhammad Ayaz Anwar
    • 2
  • Sangdun Choi
    • 2
    Email author
  1. 1.Department of Life SciencesCentral University of Tamil NaduThiruvarurIndia
  2. 2.Department of Molecular Science and TechnologyAjou UniversitySuwonKorea