Separate actions of different colony stimulating factors from human placental conditioned medium on human hemopoietic progenitor cell survival and proliferation

Abstract

More than 20% of human granulocyte‐macrophage and eosinophil colony‐forming cells survived in agar culture for up to 4 days without the addition of exogenous colony stimulating factors (human placental‐conditioned medium, HPCM). Survival was reduced slightly but not significantly, by the removal of adherent cell populations. Significant survival occurred even when only 100 cells enriched for colony‐forming cells (CFCs) were cultured per dish. When individual colonies, initiated by stimulation with HPCM for 5 days, were transferred to dishes without HPCM, subsequent proliferation was significantly reduced compared with control cultures containing HPCM. Using the fluorescence‐activated cell so..