Donors Donors were human leukocyte antigen (HLA) A,B,C serologically matched and DR and DQ molecularly matched siblings. Donor stem cells were collected following mobilization with 10 µg/kg/day G-CSF, given subcutaneously for 5 consecutive days. CD34 cells were positively selected using anti-CD34 antibody conjugated to iron-dextran microbeads using CliniMACS device (Miltenyi Biotech, Bergisch Gladbach, Germany) with an aim to collect > 5.0 x 106 CD34 cells/kg.