Article

Variable NK cell receptors exemplified by human KIR3DL1/S1.

Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
The Journal of Immunology (impact factor: 5.79). 07/2011; 187(1):11-9. DOI:10.4049/jimmunol.0902332 pp.11-9
Source: PubMed

ABSTRACT Variegated expression of variable NK cell receptors for polymorphic MHC class I broadens the range of an individual's NK cell response and the capacity for populations and species to survive disease epidemics and population bottlenecks. On evolutionary time scales, this component of immunity is exceptionally dynamic, unstable, and short-lived, being dependent on coevolution of ligands and receptors subject to varying, competing selection pressures. Consequently these systems of variable NK cell receptors are largely species specific and have recruited different classes of glycoprotein, even within the primate order of mammals. Such disparity helps to explain substantial differences in NK cell biology between humans and animal models, for which the population genetics is largely ignored. KIR3DL1/S1, which recognizes the Bw4 epitope of HLA-A and -B and is the most extensively studied of the variable NK cell receptors, exemplifies how variation in all possible parameters of function is recruited to diversify the human NK cell response.

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Keywords

Bw4 epitope
 
coevolution
 
evolutionary time scales
 
extensively
 
glycoprotein
 
human NK cell response
 
humans
 
individual's NK cell response
 
NK cell biology
 
polymorphic MHC class
 
possible parameters
 
primate order
 
receptors
 
recruited different classes
 
selection pressures
 
substantial differences
 
unstable
 
variable NK cell receptors
 
Variegated expression