Relationship Between HBV Genotypes B, C and Follicular Helper T Cells in Patients with Chronic Hepatitis B and its Significance

BACKGROUND Clinical observations have shown that patients infected with chronic hepatitis B virus (HBV) genotype C versus genotype B had a higher load of the virus, more serious illness, and poorer responses to antiviral therapy and prognosis. However, the disparity between the two has not been clarified. OBJECTIVES To explore possible relationship between HBV genotypes B and C and peripheral blood follicular helper T cells (Tfh) and its significance in treating chronic hepatitis B (CHB) patients. PATIENTS AND METHODS One hundred and fifty CHB patients were enrolled into this study, including 70 cases infected with HBV genotype C and 79 cases with genotype B. One patient had suffered from both genotypes B and C. The levels of Tfh, also known as interleukin-21 (IL-21), HBV specific cytotoxic T lymphocytes (CTL), HBV DNA and alanine transaminase (ALT) were evaluated and compared in patients infected with genotype B and C. RESULTS Levels of Tfh, IL-21 and HBV specific CTL of patients infected with HBV genotype C were significantly lower than those of patients infected with HBV genotype B, P < 0.01. Levels of HBV DNA and ALT of patients infected with genotype C were significantly higher than those of the patients infected with HBV genotype B, P < 0.01. CONCLUSIONS Compared with chronic hepatitis B (CHB) patients infected with genotype B, higher levels of serum HBV DNA, ALT and TBil of patients infected with HBV genotype C may be related to their lower level of peripheral blood Tfh, which may result in lower IL-21, and it may result in lower HBV specific CTL.