The impact of sialylation linkage-type on the pharmacokinetics of recombinant butyrylcholinesterases.

Chinese hamster ovary (CHO) cells typically produce glycoproteins with N-glycans terminating in α-2,3 sialylation. Human cells produce glycoproteins that include α-2,3 and α-2,6 sialic acids. To examine the impact of altering protein sialylation on pharmacokinetic properties, recombinant human butyrylcholinesterase (BChE) was produced in CHO cells by knocking out the α-2,3 sialyltransferase genes followed by overexpression of the α-2,6 sialyltransferase (26BChE) enzyme.

Combining Butyrated ManNAc with Glycoengineered CHO Cells Improves EPO Glycan Quality and Production.

Sodium butyrate (NaBu) is not only well-known for enhancing protein production, but also degrades glycan quality. In this study, butyrate supplied by the precursor molecule 1,3,4-O-Bu ManNAc is applied to overcome the negative effects of NaBu on glycan quality while simultaneously increasing the productivity of the model recombinant erythropoietin (EPO). The beneficial impact of 1,3,4-O-Bu ManNAc on EPO glycan quality, while evident in wild-type CHO cells, is particularly pronounced in glycoengineered CHO cells with stable overexpression of β-1,4- and β-1,6-N-acetylglucosaminyltransferases (GnTIV and GnTV) and α-2,6-sialyltransferase (ST6) enzymes responsible for N-glycan antennarity and sialylation.

Antibody glycoengineering strategies in mammalian cells.

As a key parameter impacting functional and structural heterogeneity, protein glycosylation is a critical quality attribute for antibody biotherapeutic manufacturing. The glycan patterns on recombinant antibodies, particularly on the conserved fragment crystallizable (Fc) region, can have significant effects on an antibody's functional activities including clearance rate, antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and anti-inflammatory activity. In this review, we examined specific glycan attachments (fucosylation, sialylation, galactosylation, high-mannose, and bisecting glycans) and their importance to antibody properties.