title: A sensitive new bioassay for erythroid colony-stimulating factor.
abstract: Erythroid colony-stimulating factor (E-CSF) is a B cell-derived membrane protein that specifically affects the growth and development of human and murine committed erythroid progenitors. We report the development of a sensitive new bioassay for E-CSF, based on the ability of the growth factor to stimulate 3H-thymidine incorporation into cloned Rauscher murine erythroleukemia cells. The assay has among its advantages the ability to measure growth factor activity on a purified target cell population in the absence of endogenous growth factor-producing accessory cells. In addition, this assay measures E-CSF's proliferative effect on erythroid progenitors in the absence of erythropoietin (Epo) after 72 to 96 hours. In contrast, the standard bone marrow fibrin clot assay traditionally used to measure E-CSF requires the addition of Epo to promote the development of hemoglobinized erythroid colonies that are quantified after 7 days (for murine cells) to 12 days (for human cells). With the use of this new Rauscher cell bioassay, we have identified an E-CSF-producing human cell line and, further, have measured E-CSF activity derived from nonhuman splenic B lymphocytes.
authors.affiliation: Laboratory for Cell and Molecular Biology, New England Deaconess Hospital, Harvard Medical School, Boston, MA 02215.
authors.forename: L
authors.initials: L
authors.lastname: Feldman
authors.forename: K L
authors.initials: KL
authors.lastname: Davis
authors.forename: D M
authors.initials: DM
authors.lastname: Feeley
authors.forename: A J
authors.initials: AJ
authors.lastname: Sytkowski
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D001681:Biological Assay; D002455:Cell Division; D002461:Cell Line, Transformed; D003115:Colony-Stimulating Factors / Q000032:analysis* / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D015672:Erythroid Precursor Cells / Q000166:cytology; D004920:Erythropoiesis; D004921:Erythropoietin / Q000494:pharmacology; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism / Q000473:pathology; D051379:Mice; D014407:Tumor Cells, Cultured
chemical_list: D003115:Colony-Stimulating Factors; D004921:Erythropoietin; D004247:DNA