Transplantation of CD34+ selected peripheral blood to HLA-identical sibling patients with aplastic anaemia: results from a single institution

We evaluated the use of CD34+ selected allogeneic peripheral blood as a source of hematopoietic progenitors for allogeneic transplantation in 11 patients with aplastic anemia (AA). The median age was 17 years (range, 6--9), and the median time between diagnosis and transplant 1 month (range, 1--4). Conditioning consisted of cyclophosphamide (50 mg/kg per day) on days--7 to--4 and antithymocyte globulin (30 mg/kg per day) on days--4 to--2 in nine patients. Total lymphoid irradiation was added to the preparative regimen for two. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine A and prednisone. Median doses of CD34+ and CD3+ cells infused were 3.91 x 10(6) and 0.3 x 10(6)/kg, respectively. The median time taken to achieve a neutrophil count >0.5 x 10(9)/l was 12 days and to recover a platelet count >20 x 10(9)/l, 13 days. Two patients developed acute GVHD grade I--II and one developed limited chronic GVHD. There were two treatment-related deaths. At a median follow-up of 44 months (range, 4--3), nine patients were alive with sustained and complete engraftment. This is a promising procedure in patients with AA, resulting in a rapid hematopoietic recovery, a low transplant-related mortality, and a low incidence of GVHD.