The technology relates in part to methods for inducing partial apoptosis of cells that express an inducible caspase polypeptide. The technology further relates in part to methods for inducing partial apoptosis of cells that express an inducible modified caspase polypeptide, having a modified dose response curve to the multimeric ligand inducer. The technology also relates in part to methods for cell therapy using cells that express the inducible caspase polypeptide or the inducible modified caspase polypeptide, where the proportion of caspase polypeptide-expressing cells eliminated by apoptosis is related to the administered amount of the multimeric ligand inducer.
