DEFECTIVE LYMPHOCYTES SUPPORTING HEMATOPOIESIS IN PATIENTS WITH PAROXYSMAL NOCTURNAL HEMOGLOBINURIA

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemo-lytic disease in which there is a stem cell disorder of clonal nature. Previous studies have demonstrated that the numbers of burst-forming units-erythroid (BFU-E) and colony-forming units-granulocyte / macrophage (CFU-GM) from bone marrow of PNH patients growing in the medium containing PHA-LCM from the normai donors were more reduced than those of normai bone marrow. The purpose of present study was to investigate if PNH lymphocytes are defective in supporting hematopoiesis in vitro. PHA-LCM from PNH blood was added to the culture medium for the growth of PNH and normai BFU-E and CFU-GM. The numbers of PNH bone marrow BFU-E and CFU-GM in the medium containing PHA-LCM from PNH blood were less than those from normai blood; the numbers of normai bone marrow BFU-E and CFU-GM grown in the medium containing PHA-LCM from PNH blood were more decreased than those from normai blood. The results suggest that diminished numbers of PNH bone marrovv BFU-

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemo-lytic disease in which there is a stem cell disorder of clonal nature. Previous studies have demonstrated that the numbers of burst-forming units-erythroid (BFU-E) and colony-forming units-granulocyte / macrophage (CFU-GM) from bone marrow of PNH patients growing in the medium containing PHA-LCM from the normai donors were more reduced than those of normai bone marrow. The purpose of present study was to investigate if PNH lymphocytes are defective in supporting hematopoiesis in vitro. PHA-LCM from PNH blood was added to the culture medium for the growth of PNH and normai BFU-E and CFU-GM. The numbers of PNH bone marrow BFU-E and CFU-GM in the medium containing PHA-LCM from PNH blood were less than those from normai blood; the numbers of normai bone marrow BFU-E and CFU-GM grown in the medium containing PHA-LCM from PNH blood were more decreased than those from normai blood. The results suggest that diminished numbers of PNH bone marrovv BFU-E and CFU-GM were resulted from either a proliferative abnormality or lack of response to hematopoietic growth factors, and also in part from defective lymphocytes supporting hematopoiesis.