Controlling the glycosylation of recombinant proteins expressed in animal cells by genetic and physiological engineering

The cDNA coding for rat alpha-2,6-sialyltransferase (alpha 2,6-ST) was expressed in a recombinant CHO cell line producing interferon-gamma, using a novel in vitro amplification vector. The alpha 2,6-ST was expressed efficiently, 20-30% of the sialic acid pool on interferon-gamma being linked in the alpha 2,6-conformation. Despite the overall level of sialylation was not significantly increased, growth and interferon-gamma production in bioreactor were not compromised by the transfection and expression of the gene encoding for the alpha 2,6-ST.