Donor chimerism analysis. Donor chimerism was measured by short tandem repeat analysis in peripheral whole blood and, when sufficient CD3⁺ cells were present in peripheral blood, in sorted CD3⁺ cells. Donor chimerism >95% in whole blood was seen in 81%, 83%, 76%, and 65% of patients and in 71%, 53%, 63%, and 71% for CD3⁺ cells at days (D) 100 and 180 and at 1 and 2 years posttransplantation, respectively.