Article

The control of adaptive immune responses by the innate immune system.

Howard Hughes Medical Institute, Department of Immunobiology, School of Medicine, Yale University, New Haven, Connecticut, USA.
Advances in Immunology (impact factor: 5.76). 01/2011; 109:87-124. DOI:10.1016/B978-0-12-387664-5.00003-0 pp.87-124
Source: PubMed

ABSTRACT The mammalian immune system comprises an adaptive and an innate component. The innate immune system employs a limited number of germ-line-encoded pattern-recognition receptors (PRRs) that recognize invariant pathogen-associated molecular patterns (PAMPs). In contrast, the adaptive immune system depends on the generation of a diverse repertoire of antigen receptors on T and B lymphocytes and subsequent activation and clonal expansion of cells carrying the appropriate antigen-specific receptors. Induction of adaptive immunity not only depends on direct antigen recognition by the antigen receptors but also relies on essential signals that are delivered by the innate immune system. In recent years, we have witnessed the discovery of a still expanding array of different PRR systems that govern the generation of adaptive immunity. Here, we review our current understanding of innate control of adaptive immunity. In particular, we discuss how PRRs initiate adaptive immune responses in general, discuss specific mechanisms that shape the ensuing T and B cell responses, and highlight open questions that are still awaiting answers.

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Keywords

answers
 
antigen receptors
 
appropriate antigen-specific receptors
 
B cell responses
 
B lymphocytes
 
clonal expansion
 
ensuing T
 
germ-line-encoded pattern-recognition receptors
 
limited number
 
open questions
 
PRRs
 
recent years
 
recognize invariant pathogen-associated molecular patterns
 
specific mechanisms
 
subsequent activation
 

Dominik Schenten