^a)Nonmyeloablative allogeneic HSCTs were performed according to reference [4].

Abbreviations: Hb, hemoglobin; HCST, hematopoietic stem cell transplantation; Hct, hematocrit; HLA, human leukocyte antigen; LDH, lactate dehydrogenase; RBC, red blood cell; SCD, sickle cell disease; RCE, red cell exchange.