Comprehensive Analysis of the Durability and the Quality of Humoral and T Cell Responses in SARS-CoV-2 Vaccinated and Infected Subjects

Understanding adaptive immune memory to SARS-CoV-2 is relevant for the development of vaccines and new immunotherapies. Specifically, understanding the interactions between memory B cells and T-cell subsets can shed light on persistent immune memory and its effects on antibody durability and antibody affinity. Studying the frequencies of SARS-CoV-2 memory B cells and antigen-specific T-cells 3–6 months following natural infection or vaccination would aid us in vaccine development and vaccination in infected subjects. In this study, we analyzed these responses in individuals who were hospitalized with COVID-19 (n=20), individuals who were vaccinated after COVID hospitalization (n=20), and uninfected individuals (n=40) with two doses of the Pfizer or Moderna SARS-CoV-2 vaccine. We hypothesize individuals who were vaccinated after hospitalization will have the highest frequency of memory T follicular helper cells, memory B cells and antibody durability. To accomplish this, we will analyze anti-SARS-CoV-2 antibodies, including 7 RBD variants as well as 65-cytokines in all patients via Luminex and examine frequencies of memory T follicular helper cells, persistent memory B-cells specific to SARS-CoV-2 using flow cytometry. All immune responses will be analyzed 3–6 months after hospitalization or after a second vaccination. These results show the differences in durability and quality of humoral and T cell responses between vaccinated and infected subjects. Supported by grants from NIH supplement #U19AI128910-04S1