Epistatic interactions between killer cell immunoglobulin-like receptors (KIRs) and their cognate HLA class I ligands have important implications for reproductive success, anti-viral immunity, susceptibility to autoimmune conditions and cancer, as well as for graft-versus-leukemia reactions in settings of allogeneic stem cell transplantation. Although CD8 T cells are known to acquire KIRs when maturing from naïve to terminally differentiated cells, little information is available about the constitution of KIR repertoires on human CD8 T cells. Here, we have performed a high-resolution analysis of KIR-expression on CD8 T cells. The results show that most CD8 T cells possess a restricted KIR expression-pattern, often dominated by a single activating or inhibitory KIR. Furthermore, the expression of KIR, and its modulation of CD8 T cell function, was independent of expression of self-HLA class I-ligands. Finally, despite similarities in the stochastic regulation of KIRs by the bi-directional proximal promoter, the specificity of inhibitory KIRs on CD8 T cells was often distinct from that of NK cells in the same individual. The results provide new insight into the formation of KIR repertoires on human T cells.
- Copyright © 2013 by The American Association of Immunologists, Inc.