Correction of infantile agranulocytosis (Kostmann's syndrome) by allogeneic bone marrow transplantation.

Allogeneic bone marrow transplantation has been unsuccessful as therapy for genetically determined bone marrow disorders. In patients prepared for transplantation with drugs alone long-term hematopoietic engraftment is not achieved due to the overgrowth of the infused donor bone marrow cells by residual recipient hematopoietic stem cells. Utilizing a combination of total body irradiation and antihuman thymocyte serum, the successful eradication of the abnormal hematopoietic stem cells of patients with the Wiskott-Aldrich syndrome and now infantile agranulocytosis has been achieved. Following preparation with total body irradiation and antihuman thymocyte serum a 20 month old patient with infantile agranulocytosis has complete donor hematopoietic and lymphoid engraftment one year after a histocompatible allogeneic bone marrow transplant. Prior to transplantation, this patient had no circulating or bone marrow granulocytes; following transplantation he has normal numbers of circulating granulocytes with normal in vivo and in vitro function. This therapeutic result demonstrates that genetic disorders of myeloid function can be corrected by allogeneic bone marrow transplantation following preparation with total body irradiation and antihuman thymocyte serum, and suggests that infantile agranulocytosis is due to an intrinsic defect of the pluripotent hematopoietic stem cell and not to a micro-environmental defect.