ABSTRACT
Since the outbreak of COVID-19, over 200 vaccine candidates have been documented and some of them have advanced to clinical trials with encouraging results. However, the antibody persistence over 3 months post immunization and the long-term memory have been rarely reported. Here, we report that a ferritin nanoparticle based SARS-CoV-2 RBD vaccine induced in mice an efficient antibody response which lasts for at least 7 months post immunization. Significantly higher number of memory B cells were maintained and a significantly higher level of recall response was induced upon antigen challenge. Thus, we believe our current study provide the first information about the long-term antibody persistence and memory response of a COVID-19 vaccine. This information would be also timely useful for the development and evaluation of other vaccines.