title: Analysis of granulocyte-macrophage progenitor cells in patients treated with recombinant interferon alpha-2.
abstract: The most common dose-limiting toxicity of alpha interferon has been leukopenia. It is well documented that interferon inhibits human multipotential, erythroid, and granulocyte-macrophage progenitor cells in vitro. Granulocyte-macrophage progenitor cells were evaluated by a colony-forming assay in patients treated with recombinant interferon alpha-2, and results of the assay were correlated with histologic findings in the same bone marrow aspirates and biopsy specimens from the same patients. Eleven patients received 10 million units/m2 interferon subcutaneously thrice weekly for three months. The bone marrow was evaluated on Day-3 (pretreatment) and Day 10 of treatment. Colony-forming granulocyte-macrophage cell count fell from 40.9 +/- 7.6 colonies per 10(5) cells before treatment to 9.3 +/- 1.2 at Day 10 (mean +/- SE, p less than 0.001). It is concluded that the leukopenia induced by interferon is caused by inhibition of maturation of marrow progenitor cells preventing the repopulation of the peripheral blood.
mesh_terms: D001772:Blood Cell Count; D003114:Colony-Forming Units Assay; D006098:Granulocytes / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D007370:Interferon Type I / Q000009:adverse effects*; D007970:Leukopenia / Q000139:chemically induced; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects; D013234:Stem Cells / Q000187:drug effects*
chemical_list: D007370:Interferon Type I