Unveiling the immune system ageing in single-cell resolution.

This writing serves as a commentary on the findings presented in the original manuscript by Yang et al. in 2023, published in the Journal of Leukocyte Biology (JLB). This commentary first summarizes the spatial-temporal dynamics of regulatory T-cells (T-reg) derived from mice (Tabula Muris Senis) of different ages (3M, 18M, and 24M) at different anatomical niches like lymph nodes and bone marrow. We also reported possible combinations of receptor-ligand interactions among T follicular regulatory cells (Tfr), T follicular helper cells (Tfr), and Germinal Centre (GC) B-cells, such as Calmodulin/Fas axis and PSGL-1/L-selectin axis. Then, we have elaborated on the significance of understanding aging T-reg, and have offered some possible future research directions for Yang et al., contributing to a critical analysis of their recent study. Building upon these foundations, further investigations and studies can be conducted to delve deeper into the mechanisms by which T-reg influence health upon aging, potentially unveiling novel therapeutic targets to ameliorate age-related pathogenicity.