Hemopoietic colony-forming cells in Shwachman's syndrome.

Colony-forming capacities were studied in three Japanese children with Shwachman's syndrome (chronic neutropenia and exocrine pancreatic insufficiency). Bone marrow granulocyte-macrophage colony-forming cells assayed in a soft agar culture were markedly reduced in all three cases. The cytochemical examination of granulocyte-macrophage colonies by a new technique revealed that 90% of the colonies by a new technique revealed that 90% of the colonies consisted exclusively of granulocytes. Erythroid colony-forming cells assayed in a plasma clot culture were significantly reduced in two of the three cases. Bone marrow phagocytic cells did not suppress granulopoiesis in contrast to the cases of idiopathic aplastic anemia. Moreover, the patient serum did not inhibit granulopoiesis of normal bone marrow cells. These results have been discussed with the possibility of involving the hemopoietic stem cells and other additional factors.