Figure 5.

Increased arginase expression in recipient macrophages isolated from mice with allogeneic CD4⁺CD25⁺ Tregs. The NO secretion (a) and arginase activity (b) of macrophages isolated from recipient NOD-scid mice adoptively transferred with no cells, CD4⁺CD25⁺ T cells, CD4⁺CD25⁻ T cells or both CD4⁺CD25⁺ T cells and CD4⁺CD25⁻ T cells for 3 days. The mRNA levels of iNOS (c) and arginase I (d) of the recipient macrophages from NOD-scid mice were also determined by real-time PCR. The recipient NOD-scid mice were adoptively transferred no cells, CD4⁺CD25⁺ T cells, CD4⁺CD25⁻ T cells or both CD4⁺CD25⁺ T cells and CD4⁺CD25⁻ T cells for 3 days prior to macrophage harvesting. The data are presented as the mean±s.d. (N=6). **P<0.01 compared to the indicated groups. iNOS, inducible NO synthase; NO, nitric oxide; Treg, regulatory T cell.