HBV HBV coinfection with HCV HCV alters circulating Tfh cell distribution and impairs HCV HCV neutralizing antibody responses

摘要

Abstract Hepatitis C virus ( HCV ) and hepatitis B virus ( HBV ) coinfection reciprocally influences viral replication and host defence responses. This study aimed to investigate the impact of HBV coinfection on circulating T follicular helper cell ( cT fh) distribution and the HCV neutralizing antibody ( nA b) response. HCV neutralizing antibody responses were measured in individuals with HCV monoinfection (n?=?83) and HBV / HCV coinfection (n?=?78) using the HCV pseudoparticle neutralization assay. The frequencies of cT fh cells and their subsets in HCV monoinfection (n?=?34) and HBV / HCV coinfection (n?=?30) were analysed by flow cytometry. The correlations of clinical parameters, cT fh cells and neutralizing antibody responses were analysed. Compared with HCV monoinfection, the HBV coinfection group showed significantly lower HCV neutralizing antibody responses ( P? ? 0.001) and a decreased frequency of circulating Th1‐like Tfh cells (Tfh1) ( P? = ? 0.004). In HCV monoinfection, the frequency of the Tfh1 subset was positively correlated with HCV neutralizing antibody responses ( R? = ? 0.378, P? = ? 0.03), but this correlation was lost under HBV / HCV coinfection ( R? = ? 0.115, P? = ? 0.551). In contrast, the frequency of circulating Th2‐like Tfh cells (Tfh2) was negatively correlated with the HCV neutralizing antibody responses ( R? = ? 0.404, P? = ? 0.003). Further analysis showed that HBV coinfection enhanced the Tfh2 subset composition within cT fh cells ( P? ? 0.001), which was associated with serum HB sAg in HBV / HCV coinfection ( R? = ? 0.521, P? = ? 0.003). As expected, HB sAg also exhibited an inverse association with HCV neutralizing antibody responses in HBV / HCV coinfection ( R? = ? 0.59, P? ? 0.001). In contrast to HCV monoinfection, HBV / HCV coinfection leads to altered cT fh cell distribution and impaired HCV neutralizing antibody responses, which are associated with HB sAg. These findings will be helpful for better understanding the immunopathogenesis of HBV / HCV coinfection.