Hematogones are normal B-lineage cell precursors with morphologic and sometimes immunophenotypic, similarities to neoplastic lymphoblasts. The aim of this work is to compare using flow cytometry sub-populations of B-lineage cells: normal bone marrow precursors (hematogones) and lymphoblasts. Normal bone marrow from patients with hematogones observed by optical microscopy and new cases of acute lymphoblastic leukemia of B-cell precursors were included in the study. Antibodies directed against CD19, CD10, CD45, CD34, IgM and CD22 were used. Analysis of hematogones, using CD10 x CD45 fluorescence intensity as a parameter, showed three sub-populations: immature, intermediary and mature marker expressions. CD34, IgM, TdT and CD22 marker expressions reinforced these results. The leukemic blasts cells formed a single population with positive expression for only immature antigens. In conclusion, hematogones and blast cells demonstrated different immunophenotypic profiles. Hematogones exhibit a broad spectrum of immature, intermediary and mature cells in one sample and blast cells have essentially immature features.
Hematogone; flow cytometry; acute lymphoblastic leukemia
