Skewed T-cell subsets and enhanced macrophages phagocytosis in the spleen of patients with immune thrombocytopenia failing glucocorticoids

Abstract

T-cell abnormalities are considered important in the pathogenesis of immune thrombocytopenia (ITP). Th1 polarization of the immune response in peripheral blood mononuclear cells (PBMC) has been observed in ITP patients. However, whether the polarization of T-cell subsets exists in splenocytes remains unclear. In the present study, we detected T-cell subsets and macrophage phagocytosis capacity in the spleens of ten ITP patients failing first-line treatment. Compared with traumatic patients, ITP patients had similar percentages of Th1, Tc1, and T1 (Th1 + Tc1) cells, but lower percentages of Th2 and Tc2 cells, which did not, however, reach significant difference. ITP patients had significantly lower percentages of T2 (Th2 + Tc2) cells than the control group (P = 0.035). The ratios of Th1/Th2 and T1/T2 were significantly higher in ITP patients than the control group (P = 0.025 and 0.027, respectively). Splenic macrophages from ITP patients presented significant increase in phagocytic capacity (P < 0.001). The phagocytosis rate in splenic macrophages positively correlated with the ratio of Th1/Th2 (r = 0.767, P = 0.010), but negatively correlated with percentage of Th2 cells (r = -0.804, P = 0.005). The skewed T-cell subsets and enhanced macrophage phagocytosis in the spleen may be closely related to the disease onset and status of ITP.