CHRONIC MYELOCYTIC-LEUKEMIA (CML) - FAILURE TO DETECT RESIDUAL NORMAL COMMITTED STEM-CELLS INVITRO

Abstract

Granulocytic colonies grown in culture from marrow and peripheral blood from 5 patients with Ph1[Philadelphia chromosome]-positive CML and heterozygous at the G-6-PD [glucose-6-phosphate dehydrogenase] locus were analyzed for G-6-PD in order to identify CFU-C [normal committed stem cells] that do not arise from the CML clone. The patients had both B and A enzymes in normal tissues, but their CML clones typed as B. Whereas about 50% of colonies from normal subjects heterozygous as the G-6-PD locus show type A G-6-PD and 50% type B, only 2 of the 1308 colonies from the CML patients had type A G-6-PD. Persistence of normal committed stem cells in CML was not indicated, in contrast to that in polycythemia vera, another clonal stem cell myeloproliferative disorder.