Human bone marrow progenitor cells stimulated by cord blood

Agar cultures of human bone marrow cells stimulated by cord plasma or irradiated cord blood feeder layers demonstrated the presence of a multilineage hemopoietic growth factor in cord blood. When bone marrow cultures stimulated with giant cell tumor-conditioned medium (GCT-CM) were supplemented with this cord blood-derived growth factor, total colony numbers increased by more than 50% after day 23 and persisted in culture for approximately 40 days. Marrow cultures stimulated by the cord blood-derived growth factor formed colonies of neutrophils, monocyte-macrophages, eosinophils, mast cells, and a few colonies containing a mixed cell population. The results suggest that, while GCT-CM contains granulocyte-monocyte colony-stimulating factor (GM-CSF), cord blood contains a high concentration of a multilineage hemopoietic growth factor, which may be multi-CSF.