Correlation between percentages of peripheral blood CD4 +CXCR5 +Tfh cells and those of FoxP3 +Treg cells in patients with chronic hepatitis B virus infection

Aim: To investigate the correlation between the percentages of blood CD4 +CXCR5 +Tfh cells and those of CD4 +CD25 +FoxP3 +Treg cells in patients with chronic hepatitis B virus (HBV) infection. Methods: Fresh peripheral blood samples were collected from 15 chronic asymptomatic HBV carriers (AsC), 42 chronic hepatitis B (CHB) patients, of whom 25 were seropositive and 17 seronegative for HBeAg, 11 inactive HBsAg carriers (InC), and 15 healthy controls. The percentages of CD4 +CXCR5 +Tfh cells and CD4 +CD25 +FoxP3 +Treg cells were measured by flow cytometry. Results: The percentages of CD4 +CXCR5 +Tfh cells in total CD4 +T cells isolated from AsC, HBeAg(+)CHB and HBeAg(-)CHB patients were significantly higher than that from healthy controls [17.66 (15.34%-20.56%), 21.95 (19.60%-26.32%), 22.33 (17.58%-24.85%) vs 13.67 (9.80%-15.32%), all P < 0.001]. The percentages of CD4 +CXCR5 +Tfh cells in HBeAg(+)CHB or HBeAg(-)CHB patients were elevated significantly compared to those in AsC or InC patients, 16.11 (12.33%-19.73%), P < 0.05. The percentage of CD4 +CD25 +FoxP3 +Treg cells in AsC patients was significantly higher than that in healthy controls, 7.70 (6.35%-9.13%) vs 6.53 (5.54%-7.35%), P < 0.05. Meanwhile, there was a decreasing tendency of the percentages of CD4 +CD25 +FoxP3 +Treg cells in HBeAg(+)CHB patients, 7.52 (6.09%-8.49%) compared to AsC patients. A negative correlation was found between the percentages of circulating CD4 +CXCR5 +Tfh cells and the HBV DNA load (r = -0.275, P < 0.05), while no significant correlation was found between the percentages of circulating CD4 +CXCR5 +Tfh cells and ALT or HBsAg levels. Conclusion: CD4 +CXCR5 +Tfh cells may participate in chronic HBV-related immune response, and the relative bias between CD4 +CD25 +FoxP3 +Treg cells and CD4 +CXCR5 +Tfh cells may correlate with disease activity.