Single-cell analysis of human thymus and peripheral blood unveils the dynamics of T-cell development and aging.

Age-related thymic involution is the hallmark of immune aging, leading to susceptibility to cancers and emerging pathogens such as SARS-Cov2 in the elderly. However, the precise mechanisms underlying the thymic involution and the effect on compromised peripheral T-cell function is unknown. Here by scRNA-seq and TCR-seq, we captured and analyzed cells in the thymus and peripheral blood from the young and elderly. Collectively, our data constitute the first detailed single-cell analysis of ageing-related human thymic involution and T-cell homeostasis in peripheral, providing the insights into human immune aging and potential strategies to rejuvenate the involuted thymus and compromised T-cell immunity.