Comparative Study of Regulatory T Cell Function of Human CD25⁺CD4⁺ T Cells from Thymocytes, Cord Blood, and Adult Peripheral Blood

Figure 1

Predominance of CD45RA⁺ type CD25⁺CD4⁺ T cells in CB, and existence of CD45RA⁺ and CD45RO⁺ type CD25⁺CD4⁺ T cells in APB and Thy. (a) Mononuclear cells or thymocytes were multistained with anti-CD3, anti-CD4, anti-CD8, anti-CD25, anti-CD45RA, anti-CD45RO, anti-CD62L mAbs, and PI (Table 1). The profiles were gated for PI⁻CD3⁺CD8⁻CD4⁺ cells (left and middle columns) or CD3⁺CD8⁻CD4⁺CD25⁺ cells (right column), and expression of CD45RA versus CD45RO was illustrated. Data are representative of 3 different donors. (b) APB CD4⁺ T cells were stained with anti-CD4 and anti-CD25 mAbs. On the basis of CD4 and CD25 expression, CD25^high CD4⁺ cells, CD25^intermediate CD4⁺ cells, and CD25^negative CD4⁺ cells were sorted. Each cell population was lysed and immunoblotted with anti-FOXP3 or anti-𝛽-actin Ab. FOXP3 in human PBMC was detected at a lower position than the recombinant human FOXP3 fusion protein used as positive control, since the recombinant human FOXP3 fusion protein contains approximately 4 kDa of additional peptides such as the 6xHis tag, Xpress epitope tag, and enterokinase recognition site, as described in Section 2 .

(a)

(b)