Methods are provided for contacting a target cell with a biologically active Wnt polypeptide that is coupled to a magnetic particle, for producing biologically active bead-coupled Wnt stimulator and Wnt inhibitor polypeptides, and for enriching a target cell population for Wnt responsive or DKK responsive cells. Compositions and kits for practicing the methods of the invention are also included, and generally include a biologically active Wnt stimulator polypeptide that is coupled to a magnetic particle. Compositions and kits may also include (i) a buffer that is substantially free of detergent, and/or (ii) a biologically active bead-coupled DKK polypeptide.
