Abstract
Plasma thrombomodulin (TM) level was measured in case of acute leukemia. The cases was acute non-lymphoblastic leukemia (ANLL) (n=40), acute lymphoblastic leukemia (ALL) (n=16) and others (n=4). Plasma TM level was significantly higher in the cases at acute stage than that in the cases at remission. Plasma TM level, however, was not different between the cases with and without DIC in ANLL as well as ALL. When correlation of plasma TM level was examined to the other hematological parameters, significant correlation was found to white blood cell count (r=0.627) and leukemic cell count (r=0.591), but not to FDP, D-dimer or PIC. It was suggested that the increase of plasma TM in cases of acute leukemia was not induced by complication of DIC but by the increase of white blood cells, particularly of leukemic cells.
The amount of TM of normal white blood cells was 1.2-6.5ng/107 WBC, which suggested that only the smallest fraction of plasma TM was derived from white blood cells in normal subjects. It was also suggested that the increased plasma TM in cases of acute leukemia was not derived from leukemic cells, as TM content and mRNA were markedly reduced in leukemic cells. It was concluded that the increased plasma TM in cases of acute leukemia was derived mostly from injured endothelial cells and the increase of white blood cells and leukemic cells was related to its increase.
