Efficient expression of recombinant human monoclonal antibodies in Drosophila S2 cells

• Published in: Journal of immunological methods 2007-01, Vol.318 (1), p.37-46
• Main Authors: Johansson, Daniel X., Drakenberg, Katarina, Hopmann, Kathrin H., Schmidt, Alexej, Yari, Fayezeh, Hinkula, Jorma, Persson, Mats A.A.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal - biosynthesis; Antibodies, Monoclonal - genetics; Antibody Specificity - immunology; Biological and medical sciences; Blotting, Western; Cell Line; Cell Line, Tumor; Drosophila; Drosophila - cytology; Enzyme-Linked Immunosorbent Assay; Expression vector; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Genetic Vectors - genetics; HIV-1 - immunology; Humans; Ig heavy chain; Immunoglobulin G - biosynthesis; Immunoglobulin G - genetics; Immunoglobulin Heavy Chains - biosynthesis; Immunoglobulin Heavy Chains - genetics; Immunoglobulin Light Chains - biosynthesis; Immunoglobulin Light Chains - genetics; Immunoglobulin Variable Region - genetics; MEDICIN; Medicin och hälsovetenskap; MEDICINE; Microscopy, Fluorescence; Molecular immunology; Molecular Sequence Data; Neutralization Tests; Phage display; Recombinant Proteins - biosynthesis; Single-chain Fv fragment; Techniques; Transfection; Viral Envelope Proteins - genetics; Viral Envelope Proteins - immunology
• ISSN: 0022-1759; 1872-7905; 1872-7905
• DOI: 10.1016/j.jim.2006.08.017

We have explored the Drosophila S2 cell line for expression of Ig molecules isolated as Fab or scFv cDNA from phage-displayed libraries. We present a series of vectors for inducible expression and secretion of human Ig heavy (HC) and light chains (LC), both on separate plasmids and in combination constructs. Both HC (tested as human γ 1) and LC (human κ) could be expressed separately and were secreted into the medium, confirming previous reports. When the combination vector carrying both the HC and LC cDNA, as well as when the HC and LC vectors were co-transfected, complete IgG1 was found in the medium. Transient transfection resulted in production levels of 0.5–1 mg/l. Stable cell lines could be established within 2–3 weeks. After 10–12 days of expression from such cell lines, Ig molecules accumulated and the medium contained typically 5–35 mg/l of IgG1. The IgG in these preparations was purified to more than 90% purity on protein G columns. Binding characteristics for IgG of the same clone expressed in S2 cells or mammalian cells were indistinguishable. The main advantages with this system compared to mammalian expression were its robustness and the much faster establishment of stable, high level producing cell lines.