RECONSTITUTION OF NORMAL MEGAKARYOCYTOPOIESIS AND IMMUNOLOGICAL FUNCTIONS IN WISKOTT-ALDRICH SYNDROME BY MARROW TRANSPLANTATION FOLLOWING MYELOABLATION AND IMMUNOSUPPRESSION WITH BUSULFAN AND CYCLOPHOSPHAMIDE
Three patients with Wiskott-Aldrich syndrome received transplants of marrow from their HLA-A, B, C, D identical siblings after myeloablation with busulfan [BS], 2 mg/kg per day .times. 4 days, followed by immunosuppression with cyclophosphamide [CP], 50 mg/kg per .times. 4. Sustained engraftment of lymphoid and hematopoietic elements was documented in each case. Platelet counts in excess of 100,000/mm3 were restored 20-50 days posttransplant and remain in the normal range 6-12 mo. later. Platelets exhibit normal size and in vitro aggregation. The patients produce isoagglutinins and antibodies to other polysaccharides. The use of BS in moderate dosages as a myeloablative agent, coupled with CP may offer an improved alternative to the use of lethal total body irradiation as a preparative regimen for complete correction of Wiskott-Aldrich syndrome by marrow transplantation.