Relative reconstitution CD25⁺ and FOXP3⁺ populations in CD4⁺ cells. Scatterplots indicate each cell population as a fraction of CD4⁺ cells (for flow cytometry: by gating on CD3⁺ CD4⁺ cells; for qRT-PCR: by magnetic selection of CD4⁺ cells); horizontal bars represent the median of each group. Red circles refer to patients with clinically significant (≥ grade II) aGvHD development. The gray-shaded area represents the interquartile (25%-75%) range of cell counts in donors. A 2-tailed, nonparametric Mann-Whitney test was applied to examine for differences among patient levels 30 and 60 days after transplantation. Statistically significant results are displayed. (A) PCR analysis: Pre indicates patients before transplantation (n = 12); Don, donor (n = 13); SD, selectively CD25-depleted lymphocyte product (n = 10); d30, d60, and d90, patients 30 (n = 14), 60 (n = 10), and 90 (n = 8) days after transplantation, respectively. (B-F) Flow cytometry: Pre (n = 11), Don (n = 13), SD (n = 9), d30 (n = 13), d60 (n = 8), and d90 (n = 5).