Abstract
Background: Understanding the memory T-cell response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial for assessing the longevity of protective immunity after SARS-CoV-2 infection or coronavirus disease 2019 (COVID-19) vaccination. However, the longitudinal memory T-cell response up to 8 months post-symptom onset (PSO) according to the severity of illness is unknown.
Methods: We analyzed peripheral blood mononuclear cells (PBMCs) from healthy volunteers or patients with COVID-19 who experienced asymptomatic, mild, or severe illness at 2, 5, and 8 months PSO. SARS-CoV-2 spike, nucleocapsid, and membrane protein-stimulated PBMCs were subjected to flow cytometry analysis.
Results: A total of 24 patients (7 asymptomatic, 9 with mild disease, and 8 with severe disease) and 6 healthy volunteers were analyzed. SARS-CoV-2-specific OX40+CD137+CD4+ T cells and CD69+CD137+CD8+ T cells persisted at 8 months PSO. Also, antigen-specific cytokine-producing or polyfunctional CD4+ T cells were maintained for up to 8 months PSO. Memory CD4+ T-cell responses tended to be greater in patients who had severe illness than in those with mild or asymptomatic disease.
Conclusions: Memory response to SARS-CoV-2, based on the frequency and functionality, persists for 8 months PSO. Further investigations involving its longevity and protective effect from reinfection are warranted.
Keywords: 8 months; SARS-CoV-2; T-cell; memory response; severity.
【저자키워드】 SARS-CoV-2, severity, T-cell, 8 months, memory response, 【초록키워드】 COVID-19, coronavirus disease, Coronavirus disease 2019, coronavirus, vaccination, T cells, SARS-COV-2 infection, severity, T-cell Response, severe acute respiratory syndrome Coronavirus, memory, Antigen, Peripheral blood, Reinfection, T cell, Asymptomatic, protective immunity, nucleocapsid, membrane protein, response, Patient, Peripheral blood mononuclear cells, understanding, Mild, membrane, PBMC, T-cell, respiratory, Longevity, Asymptomatic disease, CD4+ T cell, T-cell responses, protective effect, Mild disease, SARS-CoV-2 spike, memory response, Frequency, PBMCs, severe disease, PSO, mononuclear cells, severity of illness, mononuclear cell, acute respiratory syndrome, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, healthy volunteers, post-symptom onset, Flow cytometry analysis, CD4+ T-cell, cytometry analysis, memory T-cell response, greater, analyzed, healthy volunteer, patients with COVID-19, persist, with mild disease, 【제목키워드】 Human, coronavirus 2, response, longitudinal, illness, Month,