De novo Foxp3⁺ T-reg development occurs independently of LTβR. (A) Analysis of CD25⁺Foxp3⁺CD4⁺TCRβ⁺ thymocytes, with CCR7 expression to identify newly selected CCR7⁺ Foxp3⁺ T-reg. (B) Absolute numbers of CCR7⁺ and CCR7⁻ Foxp3⁺ T-reg. Data typical of at least seven mice from three separate experiments. Error bars represent SEM.