Distinct Transcriptional Control Mechanisms of Killer Immunoglobulin-like Receptors in Natural Killer (NK) and in T Cells

Authors:
Xu J, Vallejo AN, Jiang Y, Weyand CM and Goronzy JJ
In:
Source: J Biol Chem
Publication Date: (2005)
Issue: 280(25): 24277-24285
Research Area:
Immunotherapy / Hematology
Cells used in publication:
PBMC, human
Species: human
Tissue Origin: blood
Platform:
Nucleofectorâ„¢ I/II/2b
Abstract
Killer immunoglobulin-like receptors (KIR) are expressed by natural killer (NK) cells and by subsets of CD4(+) and CD8(+) T cells, which are therefore thought to be subject to similar regulatory mechanisms. Here, we show that the transcriptional machinery to express KIR is limited to NK and T cells; however, the KIR transcriptional control differs between these two types of lymphocytes. T cells selectively express transcriptional activators binding to positions -52 to -61 of the KIR promoter, whereas an AML site around position-98 is relevant for transcription in NK cells. Although KIR expression is restricted to subsets of memory T cells, our studies demonstrate that transcriptional activators for KIRs are not acquired during T cell differentiation but are already present in naive T cells, suggesting a basic role of KIRs in T cell biology. We suggest that the regulated expression of KIRs in T cells profoundly influences peripheral tolerance and antigen-specific immune responses.