Exppression And Clinical Significance Of Cd8~+Cd25~+FOXP3~+ T Regulatory Lymphocyte In Malignant Pleural Effusion

Objective To investigate the expression and clinical significance of CD8~+ CD25~+ Foxp3~+ T regulatory lymphocyte subsets in malignant pleural effusion.Methods The percentages and phenotypic features of CD8~+ CD25~+ Foxp3~+ T cells in pleural effusion(PE) and peripheral blood(PB) patients with lung cancer with malignant pleural effusion(MPE)(30 patients), pleural effusion and peripheral blood from patients with benign pleural effusion (20 patients) ,and peripheral blood from 20 healthy volunteers were determined by flow cytometry.Results The proportion of CD8~+ CD25~+ Foxp3+ T cells was significantly higher in MPE than that in benign pleural effusion (2.20±0.25% vs 0.38±0.05% P=0.018),also significantly higher than that of peripheral blood (0.52±0.06% P=0.000) ,and the proportion of CD8~+ Treg was significantly higher in the peripheral blood of patients with MPE than in that of healthy volunteers(0.52±0.06% vs 0.31±0.04% P=0.005). However, there were no significant statistical difference among these three groups (benign pleural effusion group, the peripheral blood of patients with benign pleural effusion group (0.34±0.04%) and peripheral blood of healthy volunteers )(P=0.09 ). The lower expression of CD8~+ Treg in MPE group had significantly longer overall survival time than the higher expression of CD8~+ Treg in MPE group,the median survival time were 195 days and 105days (P=0.004) . Cox regression analysis demonstrated that the expression of CD8~+ Treg in MPE and tumor size were related to poor prognostic of MPE patients(P=0.018,P=0.006)Conclusion The proportion of CD8~+ CD25~+ Foxp3~+ T cells was higher in MPE than that of peripheral blood,also higher than that in benign pleural effusion ,and the proportion of CD8~+ Treg was significantly higher in the peripheral blood of patients with MPE group than in that of healthy volunteers group. The lower expression of CD8~+ Treg in MPE group had significantly longer overall survival time than the higher expression of CD8~+ Treg in MPE group,these data suggest that CD8~+ CD25~+ Foxp3~+ T cells may contribute to lung cancer tumral immune escape and disease progression. the expression of CD8~+ Treg in MPE and tumor size were independent hazard factors of affect the prognosis of patients with MPE.