Anti-viral memory T cell responses in the absence of IgG production in a COVID-19 convalescent individual

This is the authors' abstract. We don't add key points for this paper.

Cellular and humoral immunity are both important in host defense against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although defects in SARS-CoV-2-specific T cell immunity have been found in patients with severe lung pathology, it is still largely unclear whether virus-specific T cells are sufficient for host protection. Here, we found that in a previously characterized cohort of convalescent subjects, one individual, though lacking detectable anti-viral neutralizing IgG antibodies, showed virus-specific T cell responses, both in CD4+ and CD8+ T cells. SARS-CoV-2-specific T cells in this and other individuals are maintained for up to 10 months. This study thus further supports a critical role of T cells in host defense against SARS-CoV-2, offering new insights into the design and evaluation of COVID-19 vaccines.