Carbohydrate-targeted optimization of therapeutic gonadotropins - Carbohydrate Chemistry: Chemical and Biological Approaches - page 481

Fig. 10 Co-transfection strategy
Fig. 11 Two-step transfection strategy may be viewed as the preferred strategy for using
an universal glycoengineered CHO cell line. The protein of interest shows as white in the
producer cells (red online). Labeling of sialylated membrane is in grey (green online).
Man/Neu5Ac of the product (Fig. 12). It was found that the overall level of
a2,6-sialylation of gonadotropins ranged from 60% to 90% for three
enzymes designated as STa, STb and STc. Interestingly, the glycosylation
pattern of hCG produced in glycoengineered CHO cell lines was at
variance with the bulk of an extractive placental preparation for which
the content of a2,6-linked sialic acid is much lower and the content in
immature mannose rich glycans is 2.5-fold higher (Fig. 13).
It can be easily anticipated that the pharmacokinetics of the
two preparations may be widely different. As shown in Fig. 14, the hCG