The leukocyte immunoglobulin-like receptors (LIRs): a new family of immune regulators

Abstract: Identification of a counterstructure for the human cytomegalovirus-encoded major histo-compatibility complex class I-related gene product, UL18, has led to the discovery of a novel family of immunoreceptors, termed leukocyte immunoglobu-lin-like receptors (LIRs). The LIRs are differen-tially expressed in cells of the dendritic cell, mono-cytic and lymphocytic lineages, and appear to mediate diverse roles in immune regulation. This review summarizes the expression, distribution, and signaling capacities of the LIRs and discusses possible roles of the LIRs in both inhibition and activation of the cellular responses. J. Leukoc