The aim of study was to explore the PD-1 expression on Treg cells and its association with T-NHL.137 patients newly diagnosed with T-NHL and 115 healthy controls were enrolled. The expression level of PD-1 was measured by flow cytometry at the time of diagnose and 3-8 course of treatment.Median fluorescence intensity (MFI) of PD-1 on Treg cells in T-NHL patients was significantly higher than that in healthy controls (P 0.001). MFI of PD-1 in medium/high-risk T-NHL patients were higher than that in low-risk patients (P 0.05). After treatment with Chidamide combined with chemotherapy, MFI of PD-1 significantly decreased (P 0.05). In patients with high PD-1 expression (percentage19.6% and MFI 580), EFS was significantly lower than patients with low PD-1 expression (percentage19.6% and MFI 580).The PD-1expression on peripheral blood Treg cells of T-NHL patients is related to the diagnosis, prognosis and treatment of disease.
