Effects of Cell Culture Conditions on Antibody N-Glycosylation - What Causes High Mannose 5 Glycoform

The glycosylation of recombinant antibody secreted by mammalian cells affects biological activity in vivo. However, the antibody glycosylation structures are highly variable with cell culture processes. Parameters associated with the cell line, the culture media, and process conditions are known to affect glycosylation. These effects should be better understood in order to consistently make the product with desired quality attributes at different scales.

Antibodies with high mannose glycoforms (Man 5-9) are typically present at low levels, comparing to main antibody glycoforms G0, G1, and G2. Some recent publications indicate that antibodies bearing predominantly the Man5 glycoform have some unique properties in terms of potency, immunogenicity, and plasma clearance rate.

We have studied the effects of cell culture process conditions on antibody Man 5 levels. Multiple process parameters were tested to have better understanding of how to control the product quality in the cell culture process, and improve the consistency of glycosylation profiles. Results of our studies will be presented.