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.