Recognition of microorganisms and activation of the immune response

  title={Recognition of microorganisms and activation of the immune response},
  author={Ruslan Medzhitov},
The mammalian immune system has innate and adaptive components, which cooperate to protect the host against microbial infections. The innate immune system consists of functionally distinct 'modules' that evolved to provide different forms of protection against pathogens. It senses pathogens through pattern-recognition receptors, which trigger the activation of antimicrobial defences and stimulate the adaptive immune response. The adaptive immune system, in turn, activates innate effector… 
Pattern recognition receptors and control of adaptive immunity
The roles of various PRRs in control of adaptive immunity are discussed, including Germ‐line encoded pattern recognition receptors of the innate immune system, which instruct the adaptive immune system on when and how to best respond to a particular infection.
The innate immune system in transplantation.
Overview of the immune response.
  • D. Chaplin
  • Biology
    The Journal of allergy and clinical immunology
  • 2010
Recognition of bacterial infection by innate immune sensors
Recent findings on bacterial recognition by Toll-like receptors and NLRs and the signaling pathways activated by these sensors are reviewed.
Pathogen recognition in the innate immune response.
The present review will discuss the recent progress in the study of pathogen recognition by TLRs, RLRs and NLRs and their signalling pathways.
A calculated response: control of inflammation by the innate immune system.
  • G. Barton
  • Biology
    The Journal of clinical investigation
  • 2008
An overview of these innate receptors is provided and it is suggested that the innate immune system can interpret the context of an inflammatory trigger and direct inflammation accordingly.
Fungal Immunology: Mechanisms of Host Innate Immune Recognition and Evasion by Pathogenic Fungi
This chapter will summarize the major PRRs involved in sensing fungal PAMPS and most importantly the fungal tactics to escape the host\'s innate immune surveillance and protective mechanisms.
Immune/Inflammatory Aspects
The role of innate immunity in vitiligo patho-genesis is far from being clarified, but many findings support a contribution.


Innate immune recognition.
Microbial recognition by Toll-like receptors helps to direct adaptive immune responses to antigens derived from microbial pathogens to distinguish infectious nonself from noninfectious self.
Pathogen Recognition and Innate Immunity
Intracellular pattern recognition receptors in the host response
It is apparent that Toll-like receptors, a class of membrane receptors that sense extracellular microbes and trigger anti-pathogen signalling cascades, are likely to have critical roles in health and disease.
Mast cells in the development of adaptive immune responses
Mast cells may influence the development, intensity and duration of adaptive immune responses that contribute to host defense, allergy and autoimmunity, rather than simply functioning as effector cells in these settings.
Therapeutic implications of the TLR and VDR partnership.
Toll‐like receptors, endogenous ligands, and systemic autoimmune disease
Overall, the data support the general concept of a role for TLRs in the recognition of endogenous ligands, however, the precise details of the interactions and the extent to which they may contribute to the pathogenesis of human disease remain to be clarified.
[Induction of direct antimicrobial activity through mammalian toll-like receptors].
It is shown that TLR2 activation leads to killing of intracellular Mycobacterium (M.) tuberculosis in both mouse and human macrophages, providing evidence that mammalian TLRs have retained not only the structural features of Drosophila Toll that allow them to respond to microbial ligands, but also the ability directly to activate antimicrobial effector pathways at the site of infection.
Dendritic cells and the control of immunity
Once a neglected cell type, dendritic cells can now be readily obtained in sufficient quantities to allow molecular and cell biological analysis and the realization that these cells are a powerful tool for manipulating the immune system is realized.
Nod-like proteins in immunity, inflammation and disease
An additional key function of Nod-like receptors is in inflammatory conditions, which has been emphasized by the identification of several different mutations in the genes encoding Nod1, Nod2 and NALP3 that are associated with susceptibility to inflammatory disorders.