Understanding the landscape of the SARS‐CoV‐2‐specific T cells post‐omicron surge

Abstract

Emerging evidence shows increased humoral response post‐omicron surge, but research on T cell responses is limited. This study investigated the durability, magnitude, and breadth of SARS‐CoV‐2‐spike‐specific T cell responses in 216 two‐dose vaccinated individuals pre‐ and post‐omicron surge. Post‐surge samples showed enhanced T cell responses, indicating widespread asymptomatic exposure to omicron. Further analysis of 105 individuals with multiple exposures to SARS‐CoV‐2 through boosters or infections showed that post‐omicron, two‐dose vaccinated individuals had T cell responses comparable to those of COVID‐19 convalescents or boosted individuals. Additionally, we report cross‐reactive T cell responses against omicron sub‐variants, including BA2.86, remained strong, with preserved frequencies of spike‐specific stem‐cell‐like memory T cells. In silico prediction indicates that mutated epitopes of JN.1 and KP.2 retain over 95.6% of their HLA binding capability. Overall, our data suggests that T cell responses are sustained, enhanced, and cross‐reactive against emerging SARS‐CoV‐2 variants following symptomatic or asymptomatic omicron infection.