Abstract
The first cases of coronavirus disease-19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were reported by Chinese authorities at the end of 2019. The disease spread quickly and was declared a global pandemic shortly thereafter. To respond effectively to infection and prevent viral spread, it is important to delineate the factors that affect protective immunity. Herein, a cohort of convalescent healthcare workers was recruited and their immune responses were studied over a period of 3 to 9 months following the onset of symptoms. A cross-reactive T cell response to SARS-CoV-2 and endemic coronaviruses, i.e., OC43 and NL63, was demonstrated in the infected, convalescent cohort, as well as a cohort composed of unexposed individuals. The convalescent cohort, however, displayed an increased number of SARS-CoV-2-specific CD4 + T cells relative to the unexposed group. Moreover, unlike humoral immunity and quickly decreasing antibody titers, T cell immunity in convalescent individuals was maintained and stable throughout the study period. This study also suggests that, based on the higher CD4 T cell memory response against nucleocapsid antigen, future vaccine designs may include nucleocapsid as an additional antigen along with the spike protein.
Keywords: HCoV; SARS-CoV-2; T cell immunity; cross-reactivity; long-term memory.
【저자키워드】 SARS-CoV-2, T cell immunity, cross-reactivity, HCoV, long-term memory., 【초록키워드】 COVID-19, coronavirus disease, Coronaviruses, coronavirus, immune response, Immunity, T cells, Vaccine design, Infection, severe acute respiratory syndrome Coronavirus, viral spread, CD4, healthcare worker, Spike protein, memory, Antigen, global pandemic, Humoral immunity, Cohort, T cell, Viral, Coronavirus disease-19, protective immunity, nucleocapsid, immune responses, HCoV, NL63, respiratory, convalescent, disease spread, T cell response, OC43, Antibody titers, nucleocapsid antigen, Endemic, cross-reactive, long-term memory, acute respiratory syndrome, Factor, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, study period, Chinese, convalescent individuals, T cell memory, Affect, Prevent, convalescent individual, caused, include, recruited, reported, composed, the spike protein, demonstrated, individuals, onset of symptoms, respond, 【제목키워드】 CD4, response,