Carbohydrate-targeted optimization of therapeutic gonadotropins - Carbohydrate Chemistry: Chemical and Biological Approaches - page 482

Fig. 12 Glycoprofiling of an antibody based protein over several runs of production of a
glycoengineered CHO cell line. Grey bars represent ratio Fuc/Neu5Ac and white bars the
ratio Man/Neu5Ac.
Fig. 13 Glycoprofiling of placental and glycoengineered hCG based on the binding of
specific lectins. Lectins specific for a 2,3/6-bound sialic acids (black bars: SNA, Sambucus
nigra agglutinin), a 2,6-bound sialic acids (grey bars: PSL, Polyporus squamosus lectin) and
mannose-rich oligosaccharides (white bars: GNL, Galanthus nivalis lectin).
glycoprofile is also variable depending on the ST minigene used to
generate the clone(s). It therefore appears that the method of cloning can
be optimized according to the sialic acid content of the product of
interest.
Even though the overall capacity of a glycoengineered cell line is
largely similar for all the ST used, the a2,6-sialylation of the product can
be significantly enhanced by the best appropriate enzyme variant. It may
very well be that optimizing the product/ST pair favors a better targeting
of the two entities along the secretory pathway. Further structural and
functional characterization of glycoengineered gonadotropins is ongoing
to determine if these hypersialylated hormones may generate new drug
candidates for infertility treatment.