Evolution of donor T-cell chimerism.

Spontaneous evolution of donor T-cell chimerism after BMT and changes in chimerism induced by DLI at 3 (A) and 12 (B) weeks after BMT. T-cell chimerism was determined in PBLs by flow cytometry using anti–Thy1.1-FITC and anti–Thy1.2-PE monoclonal antibodies. In left panels, venous blood was taken from resting animals at 3 (day 21) and 12 weeks (day 84) after BMT. Bars represent mean ± SE of 6 identically designed experiments (n ≥ 4/group and total n = 43 and 25 for day 21 and day 84, respectively). In right panels, venous blood was taken at week 4 (day 28) or 13 (day 91) from animals that had either been given no infusion or DLI at week 3 or week 12, respectively, after BMT. Bars represent mean ± SE of 3 to 5 identically designed experiments (n ≥ 4/group and total n = 12-22). *P < .05 for comparison between groups as tested by Kruskal-Wallis multiple comparison Z test.