Frequencies of peripheral regulatory T cells of different study groups. Frequencies of peripheral regulatory T cells were analysed in the healthy donor (Healthy), patients with chronic hepatitis B infection (CHB), and patients with hepatocellular carcinoma (HCC) before surgery (HCCb), 1-2 days (HCCa1) or about 7 days (HCCa7) after surgery. Representative flow cytometry analysis of peripheral CD4+CD25+CD127- populations were measured and presented (A). Frequency of CD4+CD25+CD127- cells of total CD4+ T cells in the peripheral blood were calculated (B). The mean ± SEM is shown,* and ** stand for P < 0.05 and 0.01, respectively.