title: In vitro actions on hemopoietic cells of recombinant murine GM-CSF purified after production in Escherichia coli: comparison with purified native GM-CSF.
abstract: Recombinant murine GM-CSF produced in Escherichia coli was purified to homogeneity and tested in parallel with purified native GM-CSF. Both recombinant and native GM-CSF stimulated granulocyte and/or macrophage colony formation by adult and fetal mouse progenitor cells, and with adult marrow cells the specific activity of the recombinant GM-CSF (25 X 10(8) U/mg) was similar to that of the native form (15 X 10(8) U/mg). At high concentrations (greater than 200 U/ml), both forms of GM-CSF also stimulated eosinophil colony formation by adult marrow cells and, at very high concentrations (greater than 800 U/ml), megakaryocyte and some erythroid and mixed-erythroid colony formation. Recombinant GM-CSF was as effective in stimulating the proliferation of the GM-CSF-dependent cell line FD as the native molecule. Both recombinant and native GM-CSF were able to induce partial differentiation in colonies of WEHI-3B myeloid leukemic cells. Recombinant GM-CSF competed effectively for the binding of 125I-labeled native GM-CSF to hemopoietic cells, and antiserum to recombinant GM-CSF also neutralized the biological activity of native GM-CSF. The bacterially synthesized GM-CSF was a slightly more effective stimulus for megakaryocyte colony formation than the native molecule. The demonstration that purified bacterially synthesized GM-CSF is biologically active in vitro now permits studies to be undertaken on the in vivo effects of this material.
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D004247:DNA; D004926:Escherichia coli / Q000378:metabolism; D006098:Granulocytes; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D007942:Leukemia, Experimental; D008264:Macrophages; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D014411:Neoplastic Stem Cells / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology*
chemical_list: D003115:Colony-Stimulating Factors; D011994:Recombinant Proteins; D004247:DNA