Differentiation and Hematopoietic-Support of Clonal Cells in Myelodysplastic Syndromes.

Studies were performed to obtain evidences on differentiating and hematopoieting potential of marrow clone-original cells in patients with myelodysplastic syndromes (MDS). Firstly, results of correlation analysis between bone marrow clonal cells and blast percentages for total 51 MDS showed that almost all cases had higher clonal (mean 48.2%) than blast proportion (mean 6.7%) (P<0.001). Wheras in 11 AML patients, mean clone/blasts desparity was nearly zero. Secondary, amount of clone-original individual cells were defined in mature hematopoietic cells, mean 45.9% in segmented granulocytes, 46.0% in orthochromatic normoblasts and 38.0% in mature megakaryocytes. In addition, FISH examination presented approximative proportions of clonal cells in peripheral blood for all 16 tested cases (mean 37.3% in blood vs 48.6% in marrow). Moreover, the neutrophils in MDSs peripheral blood oxidazed dihydrorhodamine123 (DHR) nearly as the same as neutrophils in normal donor’s circulations did, while obviously poor function-exerting were observed in neutrophils from AML blood. Of note, researches on clonality appeared an unexpectedly outcome that most of the typical morphological dysplastic cells possessed normal karyotypes. Our discoveries proposed that the biological features of MDS clones is obviously distinguished to AML clone, which perhaps provide some new consideration for MDS pathogenesis and treatment tactics.