Studies on human bone marrow stromal cells Part 2. Growth and composition of human bone marrow stromal cells in chronic myelogenous leukemia (CML), myelodysplastic syndrome (MDS) and aplastic anemia (AA)

Growth and composition of human bone marrow stromal cells (HBMSC) in CML, MDS and AA were studied by using modified Dexter's culture system. Growth was experssed by the percent of HBMSC at the bottom of the culture dish(% confluence) at the 1st, 2nd, 3rd and 4th week. Cells harvested at the 4th week, were identified by monoclonal antibodies (anti-fibronectin, anti-vWF, anti-CD14, anti-CD7, anti=CD4 and anti-CD8 antibodies) and oil red 0 staininig method. In normal healty individuals (NC), % confluence at the 1st, 2nd, 3rd and 4th week were 74±4%, 82±13%, 100% and 100% respectively (n=10). HBMSC were composed of 64±4% fibro-blastoid cells, 15±3% endothelial cells, 9±4% monocyte/macrophage, 3±2% fat cells, 7±3% T lymphocyte, 4±1% helper/inducer T cells and 4±1% suppressor/cytotoxic T cells, respec-tively (n=8). In CML (n=6), % confluence at each week were almost on the decrease in comparison with those in NC and the cells tended to be detached from the bottom at the 3rd and 4th weeks. The composition of the HBMSC were not different in comparison with those in NC. In MDS (n=4), % confluence at each week and composition of HBMSC were not different in comparison with those in NC. In 3 of the 4 AA, % confluence at each week were not different in comparison with those in NC. Fat cells were markedly increased in one of 4 cases, which clinically belonged to the severe type of AA. In the other 3 AA, the percentage of endothelial cells was increased up to 35%, 32% and 21%, respectively. The CD4/CD8 rations were not different from those in NC. These finding indicate that the pathophysiological analysis of hematological disorders should be done not only on hematopoietic stem cells but also on the hematopoietic microenvi-ronment including bone marrow stromal cells