NKT cells, in contrast to CD4+CD25+ T regulatory cells, have little effect on Tcon proliferation in vivo. Left: BLI of luc+Tcons in the presence of various quantities of NKT cells shows the expansion of Tcons in vivo to be minimally affected by NKT cells. Groups: TCD-BM only (●); 5 × 105 Tcons (▿); Tcons + 2.5 × 105 NKT (×); Tcons + 1 × 105 NKT (▵); Tcons + 5 × 104 NKT (◇); Tcons + 2.5 × 104 NKT (○); and Tcons + 1 × 104 NKT (□). Bars indicate means ± SE (n = 5). Right: Increasing numbers of CD4+CD25+ Tregs cause a dose-dependent decrease in luc+Tcon proliferation in vivo, as indicated by BLI. Groups: TCD-BM only (●); 5 × 105 Tcons (▿); Tcons + 2.5 × 105 Tregs (♦); Tcons + 1 × 105 Tregs (▵); Tcons + 2.5 × 104 Tregs (○); and Tcons + 1 × 104 Tregs (□). Bars indicate means ± SE (n = 5)
