Changes in Peripheral CD4+CD25^high Regulatory T Cells in the Acute-on-Chronic Liver Failure Patients with Plasma Exchange Treatment

The prevalence of CD4+CD25^high regulatory T cells (Tregs) in patients with acute-on-chronic liver failure (AoCLF) who received plasma exchange (PE) and/or medical treatment was investigated. One hundred five patients with AoCLF in two groups (PE plus routine-care, n = 48 and routine-care, n = 57) were enrolled in our study. In the PE group, there were 27 survivors (27/48) while, in the routine-care group, there were 18 survivors (18/57), both after 30 days treatment. Twenty-three healthy donors were used as the control group. Tregs were determined by flow cytometry serially. In the survivors, Tregs frequency were lower compared with the normal controls on admission and showed an up and down tendency; moreover, this frequency turned to the level as that in healthy subjects and was faster in the PE compared with the medical group while, among the nonsurvivors, Tregs stayed at a high level throughout the examination period. Importantly, an increased quantity of Tregs was associated with high mortality and reduced survival time of AoCLF patients. These data suggest that Tregs play a role in determining the patient’s fate toward either a favorable or unfavorable clinical course of disease, and PE may represent a reliable hepatic support device for AoCLF.