Pharmacological characterization of the chemokine receptor, hCCR1 in a stable transfectant and differentiated HL-60 cells: antagonism of hCCR1 activation by MIP-1beta.

C-C chemokine receptor-1 (CCR1) has been implicated in mediating a variety of inflammatory conditions including multiple sclerosis and organ rejection. Although originally referred to as the MIP-1alpha/RANTES receptor, CCR1 is quite promiscuous and can be activated by numerous chemokines. We used radioligand binding and [35S]-GTPgammaS exchange assays in membranes from a cell line transfected to express CCR1 (Ba/F3-hCCR1) to characterize a panel of chemokines (HCC-1, MIP-1alpha, MIP-1beta, MIP-1delta, MPIF-1, MCP-2, MCP-3, and RANTES) as CCR1 ligands.