Fig. 2.

Thymic cellularity is decreased after caloric restriction. Ten-month-old B6 mice treated by CR as in Fig. 1 were analyzed for thymus lymphocyte subset cellularity by flow cytometry. a Absolute counts of CD4 single positive, CD8 single positive, double negative, and CD4/CD8 double positive thymocytes. b Absolute count of CD4/CD8 double negative thymocyte subsets (DN1-4), based on CD44 and CD25 expression. Statistical differences were calculated by one-tailed Mann Whitney U tests by comparing cellularity to age-matched, AL fed mice. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. Data are representative of three independent experiments with 2–8 mice per treatment group