The lack of healthy HLA-identical sibs limits the use of allogeneic hematopoietic cell transplantation in children with high-risk sickle cell disease (SCD). We evaluated unrelated placental blood cell transplantation (UPBCT) after a preparative regimen of busulfan, cyclophosphamide and antithymocyte globulin in three children with SCD who had cerebrovascular accidents (CVAs) and did not have HLA-matched sib donors. The placental blood cell units were matched with the recipients at four of six HLA-A, HLA-B and HLA-DRB1 antigens. Neutrophil levels above 0.5 × 109/l occurred at 23, 38 and 42 days after UPBCT, and platelet levels above 50 × 109/l without transfusions occurred at 62, 81 and 121 days after UPBCT. All patients developed acute graft-versus-host disease (GVHD; two grade II, one grade III), and one developed extensive chronic GVHD. One patient had graft failure and autologous hematopoietic recovery. Two patients have complete donor hematopoietic chimerism without detectable hemoglobin S or symptoms of SCD at 40 and 61 months, respectively, after UPBCT. These observations demonstrate the feasibility of UPBCT in children with SCD. Further studies of UPBCT for SCD are needed but, because of risks of procedure-related morbidity and graft rejection, should be restricted to pediatric patients with high-risk manifestations of SCD.
Bibliographical noteFunding Information:
This study was supported by grants from the National Institutes of Health, Bethesda, MD (K23 HL04251) (TVA), (R01 CA40282 and U10 CA20549) (AMY), and by grants from the Emory Medical Care Foundation (TVA), the Phil Niekro Egleston Celebrity Classic/Jill Andrews Leukemia Research Fund (AMY), the Andrew McLeroy Memorial Research Fund (AMY), the Armstead-Barnhill Foundation for Sickle Cell Anemia Research (AMY) and the Stott Research Fund in Honor of Alex Jensen (AMY).
- Allogeneic hematopoietic cell transplantation
- Allogeneic transplantation
- Placental (cord blood) cells
- Sickle cell disease