Construction of a System to Monitor Recombinant Immunoglobulin Secretion in HEK 293 Cells

Abstract:

Immunoglobulin G（IgG） is one of the most important pharmaceuticals，which has been widely used in many kinds of diagnoses and therapies. To construct cell lines that can produce high amounts of recombinant antibodies，it is essential to understand factors required for the folding and secretion/transport of antibodies using a monitoring system. In this study，we established a mammalian cell line（HEK 293） to stably expressing a green fluorescent protein（GFP）-fused IgG E-F-HyHEL10，which could monitor the recombinant antibody secretion using the flow cytometry. The E-F-HyHEL10 was successfully expressed and secreted well into the medium，and could retain the antibody's biofunction. After treatment with either brefeldin A or cycloheximide，the GFP fluorescence derived from E-F-HyHEL10 in the cells was positively correlated with the level of secreted antibody. These results suggested that the modified HEK293 cells could be used flexibly to monitor the secretion of recombinant immunoglobulin in cells，and possibly can be applied for identification of factors required for antibody secretion in mammalian cells in the future.