title: Studies on chronic myeloid leukemia cell populations with colony-forming abilities in PHA-leukocyte feeder and Robinson assays.
abstract: Investigation of leukemic colony-forming cells (CFC) in PHA-supplemented cultures requires removal of T lymphocyte precursors prior to culture. Using a method of discontinuous density gradient centrifugation with concurrent depletion of E-rosette forming cells, T lymphocytes were effectively separated from light density CML bone marrow and blood cell fractions. Consequently, in light density fractions (1.056 and 1.059 g/ml) pure leukemic colony growth was obtained in the PHA-leukocyte feeder (PHA-l.f.) assay. Fraction 1.062 g/ml also yielded pure leukemic colonies in most experiments. Comparison of the density distributions of leukemic PHA-l.f. CFC and Robinson CFC revealed that both CFC populations had congruent density profiles in most patients. In others PHA-l.f. CFC were found to be of somewhat higher density than Robinson CFC. The most striking divergence was apparent in a patient in blast crisis. The findings suggest that different subsets of precursor cells within the CML population proliferate in PHA-l.f. and Robinson colony methods. Both colony techniques are thus potentially useful for discriminating subpopulations of colony-forming cells in chronic myeloid leukemia.
mesh_terms: D002455:Cell Division; D002469:Cell Separation; D002871:Chromosome Banding; D002904:Chromosomes, Human, 21-22 and Y / Q000648:ultrastructure; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D006801:Humans; D007951:Leukemia, Myeloid / Q000473:pathology* / Q000648:ultrastructure; D007962:Leukocytes; D010835:Phytohemagglutinins / Q000494:pharmacology*; D012397:Rosette Formation; D013601:T-Lymphocytes
chemical_list: D010835:Phytohemagglutinins