Purified anti-mouse Ly49D

Ly49D is a type II transmembrane protein belonging to the Ly49 family of NK-cell receptors in the C-type lectin superfamily. Ly49D is expressed on subsets of natural killer (NK) cells in C57BL/6, C3H/He and SJL mouse strains, but not Balb/c, DBA/2, AKR and CBA/J. The receptors form homodimers that bind to MHC class I alloantigens. Unlike inhibitory Ly49 family members, Ly49D lacks a cytoplasmic immunoreceptor tyrosine-based inhibitory motif (ITIM) but contains a cytoplasmic immunoreceptor tyrosine-based activation motif. The activating receptor Ly49D delivers stimulatory signals for target cell lysis upon interacting with H2-Dd, Dr and Dsp2, but not with H2b or H2k class I antigens. Cross-linking of Ly49D activates intracellular kinase activity and calcium mobilization in NK cells. In 129/J mice, 4E5 antibody cross-reacts with Ly49O, LY49R and Ly49V.