Personal Information and Interests

Education:
B.Eng. Chemical Engineering
National University of Singapore, 2000

Academic Interests

Research Interests: Glycosylation of recombinant proteins in Chinese Hamster Ovary cells
Thesis Advisors: Daniel I. C. Wang and Miranda G.S. Yap

Research Description

Glycosylation of recombinant proteins affect critical properties such as its solubility, thermal stability and bioactivity. In particular, the presence of sialic acid, the terminal sugar for N-linked glycans is known to increase its circulatory lifetime. Thus, maintaining a high and consistent degree of sialylation is one of the important goals in recombinant glycoprotein therapeutic production. The overall aim of my project is thus to enhance quality of recombinant glycoproteins by exploring ways to improve glycosylation, in particular the sialylation process in cells.

Simplified diagram of the intracellular sialylation process

Attempts to improve intracellular sialylation have included the over expression of sialyltransferases and increasing the availability of metabolic precursors required for sialylation. Each of these strategies has met with limited success. My project considers the transport of CMP-sialic acid into the Golgi as a possible factor that limits intracellular sialylation. This deficiency in transport limits the availability of CMP-sialic acid and hence the extent of sialylation that takes place. To test this hypothesis, the CMP-sialic acid transporter has been over expressed in a CHO cell line producing interferon-gamma (IFNγ). The sialylation of IFNγ has been measured to assess the effectiveness of this strategy in improving intracellular sialylation.