THP-1 SMAD/TGFbeta Reporter (Luc) cells are derived from the human monocytic THP-1 cell line by stably integration of a SMAD/TGFbeta firefly luciferase reporter construct. THP-1 cells are undifferentiated monocytes, but they can be induced to differentiate into macrophage-like cells upon treatment with agents such as phorbol 12-myristate 13-acetate (PMA), making them a useful model for studying the differentiation of monocytes into macrophages and their role in immune responses and inflammation. THP-1 SMAD/TGFbeta Reporter (Luc) cells stably express firefly luciferase under the control of the SMAD/TGFbeta response elements, can be used for monitoring the activity of TGF?/SMAD signaling pathway.