Purification and characterization of human fibroblast-derived hybridoma growth factor identical to T-cell-derived B-cell stimulatory factor-2 (interleukin-6).
Human fibroblast cultures, when stimulated with interleukin-1 (IL-1) produce a growth factor for B-cell hybridoma and plasmocytoma cell lines. The availability of both a fast-growing and high-producer cell line (MG-63 osteosarcoma cells) and of a highly sensitive and specific assay system for this hybridoma growth factor (HGF) allowed us to obtain analytically pure preparations. Crude HGF from MG-63 cells was processed through a five-step concentration and purification schedule. Sequential adsorption to controlled pore glass (CPG) beads, antibody affinity chromatography and gel filtration resulted in a 10,000-fold purification to a specific activity of 10(9) units/mg HGF. Electrophoretically pure HGF was obtained after additional purification by cation-exchange chromatography and reversed-phase HPLC. The purification procedure revealed two distinct biologically active HGF components. The amino-terminal sequence of one of the two components was determined and found to correspond to that already predicted from cDNA clones of a protein alternatively called 26-kDa protein, interferon-beta 2 (IFN-beta 2) or B-cell stimulating factor-2 (BSF-2). The first two designations (26-kDa protein and IFN-beta 2) refer to a postulated fibroblast secretory protein with so far no unambiguously defined function; the latter designation (BSF-2) refers to a T-cell product possessing differentiation stimulatory effect on B-cell lines. The reported results firmly establish that the protein is secreted by fibroblasts and reveal that it possesses B-cell growth stimulatory activity. The new designation interleukin-6 (IL-6) is proposed to resolve prescribing nomenclature confusion.
D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D005346:Fibroblast Growth Factors / Q000302:isolation & purification* / Q000494:pharmacology; D005347:Fibroblasts / Q000378:metabolism*; D006801:Humans; D006825:Hybridomas / Q000187:drug effects*; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6; D007378:Interleukins / Q000302:isolation & purification*
D007375:Interleukin-1; D015850:Interleukin-6; D007378:Interleukins; D005346:Fibroblast Growth Factors