Foxp3 induction in CD4⁺CD25⁻ T cells in biopsy specimens of B-cell NHL. Foxp3 expression was examined in CD4⁺CD25⁻ T cells stimulated with OKT3 or OKT3/anti-CD28 Ab (A) (n = 10) or with in vitro–generated DCs pulsed with or without super-Ag TSST-1 (B) (n = 3). (C) Foxp3 expression in CD4⁺CD25⁻ or CD8⁺ T cells upon activation. CFSE was used to monitor activation and proliferation (n = 6). Percentages indicate number of proliferated CD8⁺ T cells (CFSE^dim) of just the CD8⁺ cell population. (D) CD25 and Foxp3 expression determined at specific day after activation in intratumoral CD4⁺CD25⁻ T cells in B-cell NHL (n = 4).