Advanced spatial transcriptomics and TCR sequencing reveal that thymic T cell selection pressure changes with age, with positive selection weakening while regulatory T cell populations expand. This shifting immune repertoire architecture directly impacts the aging immune system's capacity to generate protective responses while maintaining self-tolerance.
Key Points
- Positive thymic selection pressure diminishes during aging process
- Regulatory CD4SP T cells increase; proliferating CD69negDN cells decrease
- TCR clonotype characteristics predict success through negative selection pathway
Longevity Analysis
The thymus orchestrates immune competence from birth through adulthood, generating the T cell repertoire that protects against infection and malignancy. This work demonstrates that aging fundamentally reshapes the selection pressures governing T cell development—weakening the signals that drive effective immune surveillance while strengthening regulatory tolerance mechanisms. The result is an immune system increasingly skewed toward tolerance over responsiveness, a trade-off that helps explain age-related vulnerability to infection and cancer, and identifies the thymic microenvironment itself as a site where aging biology can be decoded. Understanding these spatial and molecular shifts opens avenues to identify which components of thymic function can be preserved or restored, rather than accepting immunosenescence as inevitable.
Original published by Wiley Aging Cell, by Jialing Fang, Jun Lei, Peng Chen, Zaiqiao Sun, Boxiao He, Yankang Wu, Chonil Paek, Ning Wu, Yafei Huang, ZhaoKui Dan, Hui Zhang, Zijing Xu, Pengcheng Wei, Yongshun Chen, Lei Yin .