title: Purification and characterization of a mouse serum protein with growth inhibitory properties in vitro against tumor cell lines.
abstract: A factor which is responsible for the growth inhibitory properties of certain mouse sera and related to NK-activity, has been studied. The factor was isolated from hybrid B6D2F1 (C57Bl/6 x DBA/2) serum, which is histo-compatible with the mouse tumour (B16 melanoma) used and has high NK-activity. Growth inhibitory activity was measured in an in vitro assay. It was independent of complement activation. The responsive factor was isolated and characterized by ion exchange chromatography. Concanavalin A affinity chromatography, gel filtration and iso-electric focusing. It appears to be a protein and had been labelled growth-inhibitory factor (GIF). It has a molecular weight of 230 000-260 000 daltons and an iso-electric point in the pH range 4.6-5.0. It was not retained on Concanavalin A columns.
mesh_terms: D000818:Animals; D002460:Cell Line; D003167:Complement Activation; D004546:Elapid Venoms / Q000502:physiology; D004591:Electrophoresis, Polyacrylamide Gel; D006131:Growth Inhibitors / Q000302:isolation & purification* / Q000502:physiology; D006367:HeLa Cells / Q000276:immunology; D008545:Melanoma / Q000276:immunology*; D008565:Membrane Proteins / Q000302:isolation & purification* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008970:Molecular Weight
chemical_list: D004546:Elapid Venoms; D006131:Growth Inhibitors; D008565:Membrane Proteins; C016310:cobra venom factor; C031717:growth inhibitory proteins