This assay kit provides the convenience of an all-inclusive cell-based reporter assay system for M-CSFR signaling. In addition to Reporter Cells, included are an optimized culture medium for use in reviving the cryopreserved cells, a culture medium for use in preparing test sample treatments, the physiological activator M-CSF as a positive control, Luciferase Detection Reagents, and a cell culture-ready assay plate