Glycosylation of recombinant proteins can change during the culture of animal cells. Since lipid-linked oligosaccharides (LLOs) are the carbohydrate donors in N-linked glycosylation, their availability is postulated to influence the extent of glycosylation. To test this hypothesis, relative LLO and glycosylation levels in Chinese hamster ovary (CHO) cells were monitored over the course of batch culture for corresponding changes. Radiolabelling studies reveal that throughout the length of culture, intracellular LLO levels remained within a 2-fold range and overall CHO protein glycosylation varied by less than 30%. The implications of these results and hypotheses to explain the findings are discussed. / Singapore-MIT Alliance (SMA)