High-Level Expression of a Bioengineered, Cysteine-Free Hepatocyte-Stimulating Factor (Interleukin 6)-Like Protein

• Published in: Proceedings of the National Academy of Sciences - PNAS 1988-12, Vol.85 (24), p.9426-9430
• Main Authors: Jambou, Robert C., Snouwaert, John N., Bishop, Gail Abendroth, Stebbins, John R., Frelinger, Jeffrey A., Fowlkes, Dana M.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Amino acids; Animals; Antiviral Agents; B lymphocytes; B-Lymphocytes - drug effects; Base Sequence; Biological and medical sciences; Biotechnology; Cell lines; Cysteine; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; Genetic engineering; Genetic technics; Genetic vectors; Health. Pharmaceutical industry; Hepatocytes; Humans; Industrial applications and implications. Economical aspects; Interleukin-6; Interleukins - analysis; Interleukins - genetics; Interleukins - pharmacology; Liver - drug effects; Methods. Procedures. Technologies; Molecular Sequence Data; Nucleotides; Oligonucleotides; Other active biomolecules; Production of active biomolecules; Proteins; Quaternary ammonium compounds; Rats; Recombinant Proteins - analysis; Sulfates
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.85.24.9426

Hepatocyte-stimulating factor, interferon-β 2, B-cell stimulation factor 2, and hybridoma/plasmacytoma growth factor are identical proteins presently referred to as interleukin 6 (IL-6). Through the use of synthetic oligonucleotide technology, we have constructed a biologically active recombinant IL-6 (rIL-6) gene based on the sequence of a human IL-6 cDNA. The synthetic gene encodes a cysteine-free, bioengineered rIL-6 protein that is expressed at high levels in Escherichia coli as a tripartite fusion protein. Cleavage of the fusion protein with collagenase releases a 23-kDa rIL-6 protein that can be easily purified to homogeneity. We show that the rIL-6 protein displays a range of biological activities similar to those of natural human IL-6, as demonstrated by its ability to (i) protect cells from viral infection, (ii) stimulate the synthesis of fibrinogen in rat FAZA 967 cells, and (iii) induce the terminal differentiation of B cells, resulting in elevated secretion of immunoglobulin.