NFATc1 is a Necessary Transcription Factor in Polarisation of T Helper Type 2 Lymphocytes Induced by Thymic Stromal Lymphopoietin.

Thymic stromal lymphopoietin (TSLP) activates lung dendritic cells (DCs) to promote a T helper type 2 lymphocyte (Th2) response in animal models. However, the mechanism behind this process remains unclear. In this study, we investigate the role of a nuclear factor for activated T-cells 1 (NFATc1) in the TSLP-induced polarisation towards a Th2 response. A cluster of differentiated (CD)14+ peripheral blood mononuclear cells (PBMCs) and naïve T cells were isolated from blood collected from healthy human volunteers, and TSLP was used to induce DC maturation. The effects of TSLP-DCs and treatments with FK506, an NFATc1 inhibitor, on naïve T cell differentiation were monitored by measuring the interleukin (IL)-4, IL-13, and interferon-γ (IFN-γ) expression levels. In addition, the mRNA levels of T-box expression in T cells (T-bet), GATA binding protein 3 (GATA-3), TSLP, and NFATc1 were measured for the same purpose. IL-4, IL-13, and mRNA levels of GATA-3 and NFATc1 significantly increased with TSLP-DC induction (P<0.01), indicating polarization towards the Th2 response. These changes were reversed by treatment with FK506 (P<0.01). Our findings suggest that NFATc1 plays a key role in the TSLP-induced differentiation of T cells to Th2, and NFATc1 is a potential therapeutic target for treating allergic diseases.