Both CD4+ and CD8+ T cells also exhibit dysregulated response (Qin et al., 2020). Decreased levels of CD4+ regulatory cells as marked by CD3+ CD4+ CD25+ CD127low+ population was found in severe cases. Similarly, the study found decreased CD8+ suppressor T cells (CD3+, CD8+, CD28+) in severe cases. Overall, more comprehensive studies are warranted with larger cohort size, to profile local vs systemic T cell response and persistence simultaneously, and correlate these responses with disease severity in age-matched patients.