T cell effects of castration in old mice are dependent on thymic regeneration.

<p>(<b>A</b>) Total thymus cellularity and spleen T cell numbers in 9-mth old mice 3, 14 and 28 days after surgery. Inset show proliferative response of TCR-activated spleen cells from 9-mth old mice 3 days after surgery. Results are expressed as mean±SE of 4 mice per group; *p≤0.05, **p≤0.01 compared to ShCx (unpaired two-tailed Student's t test). (<b>B</b>) Total spleen, T cell and B cell numbers in 3-mth old mice 6 weeks after thymectomy. Data is expressed as mean±SE of 6 mice per group; *p≤0.05, **p≤0.01, ***p≤0.001 compared to ShTx ShCx mice; ∧∧∧p≤0.001 compared to Tx Cx mice (One-way ANOVA, Tukey post-test). (<b>C</b>) Total thymic cellularity in 2-mth (Young) and 9-mth (Aged) male mice that were either sham-castrated (ShCx) or castrated (Cx), and 9-mth female mice that were either sham-ovariectomised (ShOvx) or ovariectomised (Ovx). Data is expressed as mean±SE of 6–13 mice per group; ***p≤0.001 compared to Young; ∧p≤0.05, ∧∧∧p≤0.001 compared to ShCx or ShOvx (unpaired two-tailed Student's t test).