Immunological Memory to Covid-19

ABSTRACT The SARS-CoV-2 coronavirus pandemic has created the largest global health crisis in almost a century. It is essential to understand the immunological responses that mediate long-term protective immunity to SARS-CoV-21. To assess the durability of humoral and cellular immunity to SARS-CoV-2 in COVID-19 patients we have been collecting longitudinal blood samples from convalescent individuals over the past 18 months. To date we have consented and enrolled 461 individuals that were infected with SARS-CoV-2 into our ongoing study. This cohort includes underrepresented and underserved members of the community. It is important to note that the vast majority (>90%) of the patients in our cohort had mild to moderate disease. This more reflective of COVID-19 infection in the general population. Using this cohort, we are proposing to extend our studies for an additional year to provide an analysis of the magnitude and durability of the antibody response, and CD4 and CD8 T cell responses to SARS-CoV-2 over a three-year period. In addition, 147 patients (32%) in our cohort were diagnosed as COVID-19 "long-haulers" with post- acute sequelae of SARS-CoV-2 (PASC), with symptoms for up to 18 months after infection onset. We will continue to monitor symptoms of PASC for an additional year and determine what features of the adaptive immune response are associated with the development of PASC. This study is a productive ongoing collaboration between the Emory Vaccine Center (PI: Rafi Ahmed) and the Fred Hutchinson Cancer Center (PI: Julie McElrath). Our studies will provide insight into the duration of immunological memory in COVID- 19 convalescent patients, and determine the correlation between PASC and the adaptive immune response.