Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.

K Saito; Y Nakamura; K Waga; K Hirota; F Inoue; H Enokihara; N Nara; S Furusawa

doi:10.1016/s0925-5710(97)00107-2

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Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.

K Saito·Y Nakamura·K Waga·K Hirota·F Inoue·H Enokihara·N Nara·S Furusawa

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Abstract

We studied the effects of polymorphonuclear neutrophils (PMN) and immature myeloid cells on the granulocyte colony-stimulating factor (G-CSF) level in vitro to better understand the regulatory mechanisms of neutropoiesis. Intact normal PMN decreased the G-CSF level after incubation with recombinant human (rh) G-CSF in a time- and dose-dependent manner. The percent reduction decreased as the concentration of rhG-CSF increased. However, the cell-free PMN-conditioned medium (PMN-CM) did not decrease the G-CSF level. The intact PMN also decreased the granulocyte-macrophage (GM)-CSF level after culture with rhGM-CSF, but did not affect the monocyte (M)-CSF level after culture with rhM-CSF. Normal bone marrow (BM) immature neutrophilic cells and G-CSF-dependent acute myeloid leukemic cells (OCI/AML la) also decreased the G-CSF level, whereas K-562 cells, which have no detectable G-CSF receptors, did not affect it. Phenylarsine oxide (PhAsO), an inhibitor of endocytosis of ligand receptor complex, abrogated this decreasing effect of intact PMN and OCI/AML la cells. These findings suggest that mature and immature myeloid cells negatively regulate neutropoiesis by, at least in part, decreasing the G-CSF level probably through receptor-mediated continual absorption and metabolism of G-CSF.

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Absorption Age Factors Bone Marrow Cells Cell Adhesion Dose-Response Relationship, Drug Granulocyte Colony-Stimulating Factor Granulocyte-Macrophage Colony-Stimulating Factor Humans Leukemia, Myeloid Macrophage Colony-Stimulating Factor Neutrophils Recombinant Proteins T-Lymphocytes Journal Article

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K Saito, Y Nakamura, K Waga, K Hirota, F Inoue, H Enokihara, N Nara, S Furusawa. 1998. Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.. https://doi.org/10.1016/s0925-5710(97)00107-2

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