In recent years, cancer immunotherapy has been leaning towards personalized, T-cell mediated therapy, due to the complex background of the disease. CD19 CAR-T cells represent a cure for hematologic malignancies. The therapy, albeit successful, does not avoid side effects such as SIRS and CRS and thus requires a development of a robust and reliable regulation of CAR-T cells. With CAR-T regulation in mind, we developed a regulatory system, based on transcription factor NFAT and heterodimerization domains ABI-PYL1, DmrA-DmrC, GAI-GID1, which either activates or represses the cells in question. We show that in the presence of chemical inductors (abscisic acid, rapamycin and gibberellin) the constructs undergo heterodimerization and that engineered NFAT, competing with endogenic NFAT, binds to its regulatory site of both reporter gene (shown in HEK293-T cells) or IL-2 (shown in Jurkat cells). We also confirm, that heterodimerization systems work in cells with expressed CD19-CAR and in presence of target antigen on the surface of Raji cells.