Purkinje cells of the cerebellum express the DARC. Immunohistochemical staining of archival specimens of human cerebellum with the anti-DARC MoAb, anti-Fy6, showed high-level expression of DARC by Purkinje neurons. This staining was inhibited by a recombinant fusion protein in which the amino terminal extracellular domain of DARC was expressed in continuous translational frame with glutathione-S-transferase. Cross-linking experiments with ¹²⁵I-labeled MGSA and immunoblots with anti-Fy6 showed that MGSA and anti-Fy6 react with a protein component of cerebellar membranes with the same size and appearance on SDS-PAGE as RBC and endothelial cell DARC (data not shown).