Assessment of the Interferon-Lambda-3 Polymorphism in the Antibody Response to COVID-19 in Older Adults Seropositive for CMV.

Background: Here, we investigated the impact of IFN-lambda-3 polymorphism on specific IgG responses for COVID-19 in older adults seropositive for CMV.

Methods: Blood samples of 25 older adults of both sexes were obtained at three different times: during a micro-outbreak (MO) of SARS-CoV-2 in 2020; eight months after (CURE); and 30 days after the administration of the second dose of ChadOx-1 vaccine (VAC). The specific IgG for both SARS-CoV-2 and CMV antigens, neutralizing antibodies against SARS-CoV-2, and also the polymorphism profile for IFN-lambda-3 (rs12979860 C > T) were assessed.