Fig. 3.

Prevention of graft rejection by CD4⁺CD25⁺ T cells irrespective of origin. (A) CD4⁺CD25⁺ T cells and CD4⁺ T cells were sorted from the spleen of CBA naïve mice. A quantity of 10⁵ CD4⁺CD25⁺ T cells were injected together with 5 × 10⁴ CD4⁺ T cells into RAG1^-/- mice. The transfused mice were transplanted with BALB/c(□, n = 14), (CBA×BALB/c)F₁ (♦, n = 7), B10 (•, n = 7), and (CBA×B10)F₁ (▾, n = 7) skin grafts. The control mice transfused with CD4⁺ T cells without added CD4⁺CD25⁺ T cells readily rejected B10 (▪, n = 25) and BALB/c (▴, n = 20) skin grafts. (B) CD4⁺CD25⁺ T cells were sorted from spleens of CBA mice tolerized to B10 (▾, n = 20; •, n = 13) or BALB/c(□, n = 10; ♦, n = 21) skin grafts. A quantity of 10⁵ of these cells were injected together with 5 × 10⁴ CD4⁺ T cells from naïve mice into RAG1^-/- mice that were transplanted with B10 (▾ and □) or BALB/c (• and ♦) skin grafts. Mice transfused with CD4⁺ T cells alone rejected B10 (▪, n = 25) or BALB/c(▴, n = 20) skin grafts.