Impaired Priming of SARS-CoV-2-Specific Naive CD8+ T Cells in Older Subjects

• Published in: Frontiers in immunology Vol. 12; p. 693054
• Main Authors: Gallerani, Eleonora, Proietto, Davide, Dallan, Beatrice, Campagnaro, Marco, Pacifico, Salvatore, Albanese, Valentina, Marzola, Erika, Marconi, Peggy, Caputo, Antonella, Appay, Victor, Gavioli, Riccardo, Nicoli, Francesco
• Format: Journal Article
• Language: English
• Published: Frontiers 13.07.2021; Frontiers Media S.A
• Subjects: cellular immunity; epitopes; immune aging; Immunology; Life Sciences; naive T cells; primary responses; SARS-CoV-2; SARS-CoV-2; Immune aging; CD8+ T cells; Cellular immunity; Naive T cells; Epitopes; Primary responses
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2021.693054

Advanced age is associated with severe symptoms and death upon SARS-CoV-2 infection. Virus-specific CD8 + T-cell responses have shown to be protective toward critical COVID-19 manifestations, suggesting that suboptimal cellular immunity may contribute to the age-pattern of the disease. The induction of a CD8 + T-cell response against an emerging pathogen like SARS-CoV-2 relies on the activation of naive T cells. To investigate whether the primary CD8 + T-cell response against this virus is defective in advanced age, we used an in vitro approach to prime SARS-CoV-2-specific naive CD8 + T cells from healthy, unexposed donors of different age groups. Compared to younger adults, older individuals display a poor SARS-CoV-2-specific T-cell priming capacity in terms of both magnitude and quality of the response. In addition, older subjects recognize a lower number of epitopes. Our results implicate that immune aging is associated with altered primary SARS-CoV-2-specific CD8 + T-cell responses.