Analysis of mutant KitlSl-20Jprotein binding to c-kit-positive cells by flow cytometry. (A) Immunoblot analysis of purified WT and Kitl^Sl-20J proteins. (B) Receptor binding of 100 μL and 300 μL of Kitl^Sl-20J protein compared with 100 μL WT protein. No significant binding was demonstrated with 3-fold higher dilution of Kitl^Sl-20J protein.