In order to perform biochemical and pharmacological characterization of CXCR1, we designed several CXCR1 constructs. All constructs, including a CXCR1–Gi2a fusion protein, were produced in insect cells after infection with recombinant baculovirus. The recombinant receptors exhibited specific high-affinity binding of 125 I-labelled interleukin-8, and Scatchard transformation of the binding data indicated the presence of a population of single homogenous binding sites.