title: Production of multilineage hemopoietic growth-stimulating activities by a human melanoma cell line.
abstract: In this study, we report that conditioned medium (CM) from the human melanoma cell line Hs0294 contains growth-stimulating activity for human and murine hemopoietic progenitor cells of multiple lineages. Crude CM was assayed for hemopoietic progenitor cell growth-stimulating activity (HP-GSA) in plasma clot cultures of 10(5) C57B1/6J mouse bone marrow cells or 10(5) light-density, nonadherent human peripheral blood mononuclear cells. CM concentrations as low as 0.2% had demonstrable HP-GSA for murine and human hemopoietic progenitor cells, although peak activity for all hemopoietic progenitor cell types assayed (murine CFU-Mix, BFU-E, CFU-GM, and CFU-M and human BFU-E) was observed with 5%-10% Hs0294-CM. Growth-stimulating activity for human erythroid progenitors (BFU-E) was comparable to that produced by phytohemagglutinin-stimulated human mononuclear cell CM. Stimulation of murine hemopoietic progenitors by Hs0294-CM was comparable to the activity in pokeweed mitogen-stimulated mouse spleen cell CM. The Hs0294-CM did not contain detectable quantities of erythropoietin or interleukin 3. Human burst-promoting activity was stable through sequential freezing and thawing, heating to 50 degrees C for 1 h or 100 degrees C for 5 min, and incubation at pH 9.8 for 1 h, but lost 70% of its activity when incubated at pH 2.2 for 1 h. More than 95% of the HP-GSA was recovered in the 50%-80% fraction by (NH4)2SO4 precipitation. The HP-GSA had an estimated molecular weight of approximately 21,000. In conclusion, we have shown that a human melanoma cell line, Hs0294, produces multilineage HP-GSA.
mesh_terms: D000818:Animals; D002460:Cell Line; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003114:Colony-Forming Units Assay; D003470:Culture Media; D004815:Epidermal Growth Factor / Q000494:pharmacology; D006133:Growth Substances / Q000302:isolation & purification* / Q000494:pharmacology; D006410:Hematopoiesis / Q000187:drug effects*; D006801:Humans; D008545:Melanoma / Q000032:analysis*; D051379:Mice; D010455:Peptides / Q000494:pharmacology; D015291:Transforming Growth Factors
chemical_list: D003470:Culture Media; D006133:Growth Substances; D010455:Peptides; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors