P07.02 Regulation of CD19 CAR T- cell activation based on engineered Nuclear factor of activated T cells artificial transcription factors

Background CD19 CAR T- cells (Chimeric antigen receptor T that recognize CD19) present a therapeutic option for various malignant diseases based on their ability to specifically the selected tumour surface markers, triggering immune cell activation and cytokine production results in killing cancerous expressing specific markers recognized by CAR. The main effect of is adequate number with sequential destruction tumorous safe manner. In order increase activation, different domains were introduced into T-cells are highly efficient destruction, but may cause serious side effects can also result patient death so activity needs be carefully controlled. 1 Several attempts made influence proliferation adding growth factors, such as IL-2, patients, however this approach increasing activating no external control over again lead non-optimal effects. Different improvements designing synthetic receptors or small molecule-inducible systems etc., which regulated expansion survival cells. 2 Material Methods regulate CAR-T activity, NFAT2 artificial transcription factors prepared. full length NFAT2, one players IL2 production, key was truncated deletion its own domain. Next, we joined via Gibson assembly tNFAT2 1-593 coding sequence heterodimerization interact upon inductor heterodimerization. interaction counterparts fused strong tripartite transcriptional activator domain VPR and/or repressor KRAB resulting formation an engineered NFAT (NFAT-TF) control. To determine NFAT-TF HEK293, Jurkat human used. Results Based luciferase assay, carried out transfected HEK293 first established heterodimerization, gene regulation occurs, according appropriate functions. Findings then transferred electroporated DNA constructs, After Raji:Jurkat co-culture ELISA measurements revealed therefore controlled action NFAT-TF. same subsequent status observed retrovirally transduced T-cells. Conclusion We developed regulatory system cells, unique mechanism factor. References Bonifant CL, et al . Toxicity management T-cell therapy. Mol Ther Oncolytics 2016; 3 :16011. Wu C-Y, Remote through molecule-gated chimeric receptor. Science 2015; 80 :350. Disclosure Information D. Lainšček: None. V. Mikolič: Š. Malenšek: A. Verbič: R. Jerala: