Pharmacological and signaling analysis of human chemokine receptor CCR-7 stably expressed in HEK-293 cells: high-affinity binding of recombinant ligands MIP-3beta and SLC stimulates multiple signaling cascades.

The chemokine receptor CCR-7 is expressed in T, NK, and dendritic cells in a time-ordered and stimulus-dependent manner. Thorough analyses of the pharmacological profiles of the recombinant ligands for CCR-7, MIP-3beta/ELC/CK-beta 11, and SLC/Exodus-2/TCA4/6C-kine, using CCR-7-expressing HEK-293E transfectants determine that ligands both bind with a K(d) in the 100 pM range-10- to 100-fold greater affinities than published K(d) values. High-affinity binding of each ligand is associated with rapid mobilization of intracellular calcium and cell migration as predicted for chemokine GPCRs, and in keeping with more recent evidence, robust activation of mitogen-activated protein kinase (MAPK).