Fig. 5.

SLO microenvironment failed to maintain T cells generated in early life during aging under steady-state condition. (A) Pictorial representation of experimental strategy to label T cells generated (time-stamped cells) at 2 to 3 mo of age (time where Cre-expressed), wherein TCRδ^CreER.TdTomato mice were fed on TAM chow for 30 d starting at 2 mo of age and thereafter lifelong maintained on normal chow before analyzing the TdTomato⁺ time-stamped cells by FCM at indicated timeline ages under homeostatic condition. (B–E) Absolute numbers of (B) total TdTomato⁺ time-stamped cells and (C) TdTomato⁺ time-stamped cells with naive (CD62L^hiCD44^lo), (D) central memory (CD62L^hiCD44^hi), and (E) virtual memory (CD62L^hiCD44^hiCD49d^lo) phenotype in the inguinal and brachial LNs, spleen, and circulation are shown. Data represent pooled results of a longitudinal experiment performed across five independent harvests with 11 to 18 mice/age group (A–E). Error bar represents mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, ****P ≤ 0.0001 (P values for CD4⁺ and CD8⁺ T cells are denoted by gray and black stars, respectively); one-way ANOVA followed by Dunnett’s multiple comparison test (compared to 3 to 4 mo) (B–E).