Engineering lepidopteran insect cells for sialoglycoprotein production by genetic transformation with mammalian beta 1,4-galactosyltransferase and alpha 2,6-sialyltransferase genes

Recombinant mammalian glycoproteins produced by the baculovirus-insect cell expression system usually do not have structurally authentic glycans. One reason for this limitation is the virtual absence in insect cells of certain glycosyltransferases, which are required for the biosynthesis of complex, terminally sialylated glycoproteins by mammalian cells. In this study, we genetically transformed insect cells with mammalian beta 1,4-galactosyltransferase and alpha 2,6-sialyltransferase genes. This produced a new insect cell line that can express both genes, serve as hosts for baculovirus infection, and produce foreign glycoproteins with terminally sialylated N-glycans.