This technology part is related to the method for controlling the activity of therapeutic cells using molecular switch or eliminating therapeutic cells, and the molecular switch uses different heterodimerization agent ligands, in conjunction with other polymer ligands. This technology for example can be used to activate or eliminate the cell for promoting implantation, for treating disease or the patients condition, or the activity of the therapeutic cells for controlling or regulating expression Chimeric antigen receptor or recombinant t cell receptors.