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The MHC class I binding proteins LIR-1 and LIR-2 inhibit Fc receptor-mediated signaling in monocytes

Abstract

The MHC class I binding proteins leukocyte immunoglobulin-like receptor (LIR)-1 and -2 recognize a similar broad spectrum of HLA-A, -B and -C alleles but are differentially expressed in lymphocytes, monocytes, and dendritic cells. In monocytes, phosphorylation of LIR-1 and LIR-2 results in the binding of the tyrosine phosphatase SHP-1. Coligation of either LIR with Fcgamma receptor I (CD64) inhibits tyrosine phosphorylation of the associated Fc receptor gamma chain and Syk molecules, as well as intracellular calcium mobilization. These findings suggest that LIR-1 and LIR-2 function as unique MHC class I receptors involved in the inhibition or down-modulation of monocyte activation signals, particularly those mediated through the receptors for IgG, IgE and IgA.

Authors: Fanger NA, Cosman D, Peterson L, Braddy SC, Maliszewski CR, Borges L
Journal: Eur J Immunol 28(11): 3423-34
Year: 1998
PubMed: Find in PubMed