Fc-mediated immune effector functions elicited by recombinant and live-attenuated herpes zoster vaccines

Background The role of Fc-mediated immune responses in protecting against herpes zoster remains poorly understood. This study aimed to evaluate the Fc-mediated immune responses of anti-VZV glycoprotein E antibodies induced by two licensed varicella-zoster virus vaccines.Research design and methods We established two cohorts, each consisting of 48 healthy participants aged 50 or above, who received either the ZVL or RZV. Serum samples were measured to evaluate the Fc-mediated immune responses for antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and antibody-dependent neutrophil phagocytosis (ADNP) against VZV-gE. The correlations between Fc-mediated functions and the IgG levels were also analyzed.Results Both ZVL and RZV significantly induced Fc effector function responses against HZ in participants after vaccination. Compared with ZVL recipients, RZV recipients exhibited significantly higher increase-fold of ADCC responses (ZVL: 1.93-fold; RZV: 8.44-fold, p < 0.001). In each vaccine group, the younger recipients showed higher ADCC responses than did the older (ZVL: 2.17-fold vs. 1.45-fold, p = 0.0136; RZV: 8.93-fold vs. 7.43-fold, p = 0.0677). Similar patterns were observed for ADCP and ADNP responses.Conclusion RZV induced superior Fc effector functions of VZV-gE antibodies compared to ZVL did. Older adults exhibited weaker Fc-mediated responses compared to younger adults following vaccination.