SIMULTANEOUS PRODUCTION OF G-CSF AND M-CSF BY AN ORAL-CANCER CELL-LINE AND THE SYNERGISTIC EFFECTS ON ASSOCIATED LEUKOCYTOSIS

We established a novel cell line, TSU, from an oral cancer patient wit h marked leucocytosis. The culture supernatant of TSU cells promoted g ranulocytic colony formation by mouse bone marrow cells, indicating th at TSU produced granulocyte-colony stimulating factor (G-CSF). The con centration of G-CSF was 2.45 mu g/mg protein, measured by enzyme-linke d immunosorbent assay (ELISA). The maximum number of colonies induced by TSU culture supernatant was more than that achieved with recombinan t human G-CSF (rhG-CSF) and the size of the colonies induced by TSU su pernatant was obviously larger than those achieved with rhG-CSF. The a ctivity of TSU supernatant was completely inhibited by antihuman G-CSF and macrophage-colony stimulating factor (M-CSF) antibodies, but was only partially inhibited by antihuman G- or M-CSF antibody alone. Thes e results indicate that not only G-CSF but also M-CSF, both of which c ould be produced by TSU cells, are involved in causing leucocytosis; t he results suggest that the synergistic production of G- and M-CSF cou ld play an important role in the leucocytosis associated with oral can cer.