Age-associated defect in ADCC response to COVID-19 vaccine

We investigated age-associated effects of SARS-CoV-2 vaccination in elderly individuals (n = 50, mean age 79) after six SARS-CoV-2 vaccine doses. While neutralization titers remained comparable across age groups, Fc-mediated effector functions declined with age. Individuals >80 demonstrated reduced antibody-dependent cellular cytotoxicity (ADCC), via a surrogate ADCC-signaling assay, correlating with diminished IgG1 binding. These findings highlight age-related impairments in Fc-mediated responses, with implications for immune protection and vaccine strategies in older populations.